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| | [[Image:Corvette C6R Road America 3.jpg|thumb|right|250px|One of [[Corvette Racing]]'s C6.Rs, driven by [[Jan Magnussen]] and [[Johnny O'Connell]].]] |
| The [[Chevrolet]] '''big block''' is a series of large displacement [[V8]] engines that were developed in the [[USA]] during the 1950s and 1960s. As American automobiles grew in size and weight following the [[Second World War]] the engines powering them had to keep pace. Chevrolet had introduced their popular [[GM Small-Block engine|small block V8]] in 1955 but needed something larger to power their medium duty trucks and the heavier cars that were on the drawing board. The decision was made by [[Chevrolet]] to develop an all-new design for large-displacement use. This engine family had two generations, the "W" series, and the Mark IV series.
| | The '''Chevrolet Corvette C6.R''' is a [[grand tourer]] [[racing car]] built by [[Pratt & Miller]] and [[General Motors]] for competition in [[endurance racing (motorsport)|endurance racing]]. It is a replacement for the [[Chevrolet Corvette C5-R|Corvette C5-R]] racing car, applying the body style of the new [[Chevrolet Corvette C6|C6 generation]] [[Chevrolet Corvette]] as well as improvements to increase the speed and reliability on the track. Since its debut in 2005, it has continued on from the previous dominance of the C5-R in its racing class with multiple [[American Le Mans Series]] championships and race wins in the [[Le Mans Series]], [[FIA GT Championship]], and [[24 Hours of Le Mans]]. |
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| ==Generation 1: "W" Series== | | ==Development== |
| The first ever production big block V8 Chevrolet engine was the "W" series, released in 1958 for passenger car and truck use. This engine was an overhead valve design, with offset valves and unique scalloped rocker covers, giving it a distinctive appearance. The "W" series was produced from 1958 to 1965, with three displacements offered: {{convert|348|cuin|L|1}}, available from 1958 to 1961 in cars and through 1964 in trucks; {{convert|409|cuin|L|1}}, available from 1961 to 1965; and {{convert|427|cuin|L|1}}, available only in 1963.
| | Having already established the C5-R as a winning car, the development of the C6.R was more of an evolution of a design rather than an all new car which required long periods of testing and design. Pratt & Miller's process was aided by the fact that, unlike the C5-R which debuted several years after the C5 generation Corvette was on the streets, the C6.R and C6 generation Corvettes would be developed at the same time. This meant that design elements which would help the race car could be adapted to the road car, allowing the C6.R to use more exotic design features but still meet homologation requirements. In turn, this meant racing elements could be adapted to the Corvette Z06 performance car, which the C6.R shares it exterior styling with. |
| | [[Image:Corvette C6.R Atlanta esses.jpg|thumb|left|250px|A rear-view of a C6.R, showing the [[air conditioner]] exhaust fan located in the center of the bodywork.]] |
| | Much of the framework of the road legal C6 was retained on the C6.R, leading to increased use of weight-saving [[aluminium]]. The road car would also replace the C5's pop-up headlights with permanent designs integrated into the bodywork. This meant that the racing car would have better air flow over the front of the car, doing away with their replacements for the pop-up headlights which stuck out of the bodywork. The large grill opening on the car would also serve to eliminate the variety of openings on the C5-R to feed not only the brake cooling ducts, but also help with downforce by exiting back out the top of the bonnet. |
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| As was the norm at the time, the "W" engine was of cast iron construction. The block had {{convert|4.84|in|mm|adj=on}} bore centers, two-bolt main bearing caps, a "side oiling" lubrication system (main oil gallery located low on the driver's side of the crankcase) with full flow oil filter, and interchangeable cylinder heads. Heads used on the high performance 409 and 427 engines had larger ports and valves than those used on the 348 and the base 409 passenger car and truck engines, but externally were identical to the standard units. One minor difference between the 348 and 409/427 was the location of the engine oil dipstick: it was on the driver's side on the former and passenger's side on the latter. No satisfactory explanation was ever presented for why this seemingly useless change was made. However, it was a fairly reliable way to differentiate between the smaller and larger versions of the engine.
| | Underneath, the C6.R retained much of the mechanical elements from the C5-R. The same Katech-built 7.0 litre V8 was used, but more closely based on the [[GM LS engine|LS7]] from the Z06. This engine, known as the ''LS7.R'', would go on to earn the Global Motorsports Engine of the Year award in 2006 for its performance and endurance capabilities. Like the C5-R, the C6.R lacked a rear window due to structural framework and fuel tanks taking up the space behind the cockpit. However, an innovation on the C6.R was the addition of a small video camera into the rear bumper, and a monitor placed on the roof of the cockpit. This allowed the drivers a better view behind them, instead of having to rely on their side mirrors. |
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| As with the 265 and 283 cubic inch small block engines, the "W" engine valve gear consisted of tubular steel push rods operating stud-mounted, stamped steel rocker arms. The push rods also acted as a conduit for oil flow to the valve gear. Due to the relatively low mass of the valve train, mechanical lifter versions of the "W" engine were capable of operating at speeds well beyond 6000 [[revolutions per minute|RPM]].
| | Another innovation was the use of an [[air conditioning]] system in the car in order to help drivers better endure high cockpit temperatures. This required the addition of a large suction fan to the rear of the car, as well as intakes integrated into the side mirrors. One innovation which the C6.R debuted in 2007 was the use of [[variable displacement]]. This system would disable half of the cylinders in the engine during caution periods in order to increase fuel economy when speed was not important. Although the system was tested during the season, its failure at the [[2007 24 Hours of Le Mans]] led the team to remove it from the cars until it could be further evaluated. |
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| Unlike many of its contemporaries, the "W" combustion chamber was in the upper part of the cylinder, not the head, the latter which only had tiny recesses for the valves. This arrangement was achieved by combining the use of a cylinder head deck that was not perpendicular to the bore with a crowned piston, a novel concept in American production engines of the day. As the piston approached [[top dead center]], the angle of the crown combined with that of the head deck to form a wedge shaped combustion chamber with a pronounced [[quench area]]. The spark plug protruded vertically into this chamber, which tended to cause a rapidly moving flame front during combustion.
| | As of the end of the 2007 season, six C6.Rs had been built by Pratt & Miller. A seventh car, used for development work, was actually built on a C5-R chassis but adapted to carry C6.R bodywork. This car has never raced and is used merely as a show car, making its public debut alongside the C6 Corvette at the 2005 [[North American International Auto Show]]. |
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| The theory behind this sort of arrangement is that maximum [[BMEP|brake mean effective pressure]] is developed at relatively low engine speeds, resulting in an engine with a broad [[torque]] curve. With its relatively flat torque characteristics, the "W" engine was well-suited to propelling both trucks and the heavier cars that were in vogue in the USA at the time of the engine's development.
| | ==Racing history== |
| | ===Corvette Racing=== |
| | [[Image:Le Mans 2005 CorvetteC6R.jpg|thumb|right|200px|A C6.R driving down the pit lane during the [[2005 24 Hours of Le Mans]].]] |
| | [[Image:Corvette C6R St Pete.jpg|thumb|right|200px|The C6.R in 2008, now running [[E85]] [[ethanol]] fuel.]] |
| | Following the retirement of the C5-R at the end of 2004, the factory Corvette Racing squad started 2005 with two brand new C6.Rs. Unlike the previous car, which had only ran select events until it could be proven quick and reliable, the C6.Rs would compete in the full [[American Le Mans Series]] season in their first year. The season did not begin as Corvette Racing had planned however, as the equally new [[Prodrive]] [[Aston Martin DBR9]] managed to win the event, earning Corvette Racing their first loss since the end of 2003. Prodrive returned to Europe after Sebring, and Corvette Racing was able to earn wins in each of the succeeding races that season. Even when Prodrive returned for the final two rounds, the improved Corvettes continued their streak and won both races. The C6.Rs also ventured to Europe for the [[24 Hours of Le Mans]], where the team were able to outlast the quicker DBR9s to earn a 1-2 victory and finish fifth and sixth overall. |
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| The "W" had a dry weight of approximately {{convert|665|lb|kg|0}}, depending on intake manifold and carburetion, and was a physically massive engine compared to its small block predecessor. | | In 2006, Prodrive chose to concentrate on the American Le Mans Series, giving Corvette Racing a battle throughout the season. Corvette Racing avenged their loss at Sebring, but Aston Martin managed their own victories later in the season. The two teams were close in the points championship throughout the season, before Corvette Racing managed to earn a three-point margin in the last race and won their second straight championship. At Le Mans, the Aston Martins once again faltered with reliability problems after leading the event, allowing a Corvette C6.R to finish the race fourth overall and win the GT1 class. |
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| ===348===
| | Following the 2006 season, Prodrive returned to Europe to concentrate on improving the DBR9 for Le Mans. This meant that Corvette Racing was left without a major opponent in the American Le Mans Series, and in fact were the only competitors in the GT1 class for nine out of twelve races that year, and easily allowing Corvette Racing to earn their third championship. At Le Mans, the Corvettes were not able to repeat their previous success as Aston Martin was finally able to reliably maintain their pace over 24 hours and earn their first class victory, leaving Corvette Racing with second. |
| {| class="wikitable" style="font-size:97%;" align="right"
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| !First<br />Year
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| |1958||1961||Turbo-Thrust||4 barrel||{{convert|250|hp|abbr=on}}
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| |1958||1961||Super Turbo-Thrust||"Tri-Power" 3x2 barrel||{{convert|280|hp|abbr=on}}
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| |1958||1961||Special Turbo-Thrust||4 barrel||{{convert|305|hp|abbr=on}}
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| |1958||1960||Special Super Turbo-Thrust||"Tri-Power" 3x2 barrel||{{convert|315|hp|abbr=on}}
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| |1959||1960||Special Turbo-Thrust||4 barrel||{{convert|320|hp|abbr=on}}
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| |1959||1961||Special Super Turbo-Thrust||"Tri-Power" 3x2 barrel||{{convert|335|hp|abbr=on}}
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| |1960||1961||Special Turbo-Thrust||4 barrel||{{convert|340|hp|abbr=on}}
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| |1960||1961||Special Super Turbo-Thrust||"Tri-Power" 3x2 barrel||{{convert|350|hp|abbr=on}}
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| The first iteration of the "W" engine was the 1958 "Turbo-Thrust" {{convert|348|CID|L|1|adj=on}} originally intended for use in Chevrolet trucks, but also introduced in the larger, heavier 1958 passenger car line. Bore was 4.125 in (104.8 mm) and stroke was 3.25 in (82.5 mm), resulting in a substantially [[oversquare]] design. This engine was superseded by the [[#409|409]] as Chevrolet's top performing engine in 1961 and went out of production for cars at the end of that year. It was produced through 1964 for use in large Chevrolet trucks.
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| With a four-barrel [[carburetor]], the base Turbo-Thrust produced 250 hp (186 kW). A special "Tri-Power" triple-two-barrel version, called the "Super Turbo-Thrust" produced 280 hp (209 kW). A "Special Turbo-Thrust" upped the output to 305 hp (227 kW) with a single large four-barrel. Mechanical lifters and the three two-barrel carburetors brought the "Special Super Turbo-Thrust" up to 315 hp (235 kW). For 1959 and 1960, high-output versions of the top two engines were produced with 320 hp (239 kW) and 335 hp (250 kW) respectively. In 1961, power was again increased to 340 hp (253 kW) for the single four-barrel model, and 350 hp (261 kW) when equipped with three two-barrels.
| | In order to honor Canadian driver [[Ron Fellows]], Corvette Racing entered a third C6.R at the [[2007 Grand Prix of Mosport|Grand Prix of Mosport]]. This third car was painted in white and red colors to match the Ron Fellows Edition Corvette Z06, a limited edition road car in honor of Fellows's involvement with the Corvette Racing program since its inception. Ron Fellows drove the car for his home race. |
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| ===409===
| | Corvette Racing plans to continue to run the C6.Rs in the American Le Mans Series and at the 24 Hours of Le Mans in 2008. |
| A {{convert|409|CID|L|1|adj=on}} version was Chevrolet's top regular production engine from 1961 to 1965, with a choice of single- or dual-four-barrel carburetors. Bore and stroke were both up from the 348 at 4.312 in (109.5 mm) by 3.50 in (88.9 mm). On [[December 17]], [[1960]], the 409 engine was announced along with the Impala SS (Super Sport) model. The initial version of the engine produced 360 hp (268 kW), with a single-four-barrel Carter AFB carburetor. The same engine was upped to 380 hp (283 kW) in 1962. A 409 horsepower (305 kW) version of this engine was also available, developing 1 hp per cubic inch with a dual-four-barrel aluminum intake manifold and two Carter AFB carburetors.
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| In the 1963 model year, output reached 425 hp (317 kW) at 6200 rpm with the 2X4 setup, 11.25:1 compression and a solid lifter camshaft. This engine was immortalized in the [[Beach Boys]] song titled "[[409 (song)|409]]". The engine was available through mid 1965 when it was replaced by the 396-cubic-inch 425 hp (317 kW) Mark IV big-block engine. In addition, a 340 hp (253 kW) version of the 409 engine was available from 1963–1965, with a single-four-barrel cast-iron intake mounting a Rochester 4GC carburetor, and a hydraulic-lifter camshaft.
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| ===427 (Z11)=== | | ===Privateer teams=== |
| A special {{convert|427|CID|L|1adj=on}} version of the 409 engine was used in the 1963 [[Chevrolet Impala]] ''Sport Coupe'' ordered under Chevrolet [[Regular Production Option|Regular Production Option (RPO)]] Z11. This was a special package created for drag racers, including aluminum engine and body parts and a cowl-induction air intake system, along with the 427 engine. The aluminum body parts were fabricated in [[Flint, MI]] at the facility now known as GM Flint Metal Center[http://www.gmdynamic.com/company/gmability/environment/plants/facility_db/facility_summary.php?fID=146]. Unlike the later second generation 427, it was based on the W-series 409 engine, but with a longer 3.65 in (92.7 mm) stroke. A high-rise two piece aluminum intake manifold and dual Carter AFB carbs fed a 13.5:1 compression ratio to produce an under-rated 430 hp (321 kW) and 435 ft·lbf (590 N·m). 50 RPO Z11 cars were produced at the Flint plant. GM Documents exist that show 50 Z11 engines were built at the GM Tonawanda engine plant for auto production, and 20 partial engines were made for replacement/over the counter use. No evidence from GM has been found that show 57 cars were built.
| | Like the C5-R, C6.Rs which had been used by the factory team eventually ended up in the hands of privateers once they were replaced by newer chassis. Unlike before, these Corvettes were sold less then a year after they had debuted, rather than the four years it took for a C5-R to be sold to another team. |
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| ==Generation 2: Mark IV Series==<!-- This section is linked from [[Chevrolet]] --> | | ====GLPK-Carsport==== |
| Development of the second generation big-block started with the so-called Mystery Motor used in Chevrolet's 1963 [[Daytona 500]] record-setting stock cars. This "secret" engine was a substantially modified form of the "W" engine, and was subsequently released for production use in mid-1965 as the Mark IV, referred to in sales literature as the "Turbo-Jet V8."
| | [[Image:GLPK Corvette.jpg|thumb|right|250px|GLPK-Carsport's C6.R running in the [[2006 FIA GT Dubai 500km]].]] |
| | Buying one of the two C6.Rs used by Corvette Racing during the 2005 season, GLPK-Carsport added this chassis to their stable to replace their C5-R in the [[FIA GT Championship]]. The driving team of Bert Longin, Anthony Kumpen, and Mike Hezemans drove the car throughout the season, and were able to score a victory at [[2006 FIA GT Paul Ricard 500km|Paul Ricard]] as well as a third place finish at the [[2006 Spa 24 Hours|Spa 24 Hours]]. The team eventually ended the season in fifth place in the championship. |
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| Where the Mark IV differed from the "W" engine was in the placement of the valves and the shape of the combustion chambers. Gone was the chamber-in-block design of the "W" (which caused the power curve to drastically sag above 6500 RPM), and in its place was a more conventional wedge chamber in the cylinder head, which was now attached to a conventional 90 degree deck. The valves continued to use the displaced arrangement of the "W" engine, but were also inclined so that they would open away from the combustion chamber and cylinder walls, a design feature made possible by Chevrolet's stud mounted rocker arms. This alteration in valve placement resulted in a significant improvement in [[volumetric efficiency]] at high RPM and a substantial increase in power output at racing speeds. Owing to the appearance of the compound angularity of the valves, the automotive press dubbed the engine the "porcupine" design.
| | For 2007, GLPK Carsport was split into Carsport Holland and PK-Carsport. PK-Carsport returned to running the C5-R they ran in Belcar to FIA GT, while Carsport Holland took over the C6.R. |
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| As part of the head redesign, the spark plugs were relocated so that they entered the combustion chamber at an angle relative the cylinder [[centerline]], rather than the straight in relationship of the "W" engine. This too helped high RPM performance. Due to the new spark plug angle, the clearance provided by the distinctive scalloped valve covers of the "W" model was no longer needed, and wide, rectangular covers were used.
| | ====Carsport Holland==== |
| | Continuing where the former GLPK-Carsport had left off, Carsport Holland's Mike Hezemans and partner Phoenix Racing's [[Jean-Denis Délétraz]] improved on the C6.R's position the previous season. |
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| In all forms (except the ZL-1 [[Can-Am]] model) the "rat motor", as it was later nicknamed (the small-block engine being a "mouse motor"), was slightly heavier than the "W" model, with a dry weight of about 685 pounds (310.7 kg). Aside from the new cylinder head design and the reversion to a conventional 90 degree cylinder head deck angle, the Mark IV shared many dimensional and mechanical design similarities with the "W" engine. The cylinder block, although more substantial in all respects, used the same cylinder bore centers and main bearing dimensions as the older engine (in fact, the shorter stroke 348 and 409 crankshafts could be installed without modification). Like its predecessor, the Mark IV used crowned pistons, which were [[casting]]s for conventional models and [[impact extruded]] ([[forge]]d), [[solid skirt]] types in high performance applications.
| | Carsport Holland won the [[2007 Spa 24 Hours|Spa 24 Hours]]. Joined by [[Marcel Fässler (racer)|Marcel Fässler]] and [[Fabrizio Gollin]], the team was able to fend off the [[Vitaphone Racing]] [[Maserati]] and earn Corvette's first victory at the endurance event. Carsport Holland earned one final victory at [[2007 FIA GT Nogaro 2 Hours|Nogaro]] before closing the season fourth in the teams' championship and third in the drivers' championship. |
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| Also retained from the "W" design were the race-proven Moraine M400 aluminum bearings first used in the 409, as well as the highly efficient "side oiling" lubrication system, which assured maximum oil flow to the main and connecting rod bearings at all times. These features, along with the robust crankcase design, sturdy forged steel crankshaft and massive four bolt main bearing caps used in the high performance versions, resulted in what many have considered to be the most rugged and reliable large displacement automotive V8 engine design of all time.
| | ====PSI Experience==== |
| | At the same time that GLPK-Carsport purchased an ex-factory C6.R, PSI Experience also bought a C6.R to add alongside their C5-R. PSI Experience chose to concentrate their efforts on the French [[FFSA GT Championship]] as well as joining the [[Le Mans Series]]. The team earned one victory at Lédenon for FFSA, while a third at the [[2006 1000km of Spa|1000 km of Spa]] was their best result in the LMS. PSI also chose to enter a few FIA GT rounds, most notably the Spa 24 Hours. The team finished fifth in the event, before joining FIA GT once again at [[2006 FIA GT Paul Ricard 500km|Paul Ricard]] and finishing second behind GLPK-Carsport's C6.R. |
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| ===396 and 402===
| | For 2007, PSI's C6.R was entered mostly in FFSA GT events, while select appearances in FIA GT as well as the 24 Hours of Le Mans were made. PSI once again managed a sole win in FFSA, winning at the final round at [[Circuit de Nevers Magny-Cours|Magny-Cours]]. Their best FIA GT result was a second place at the season opener in [[2007 FIA GT Zhuhai 2 Hours|Zhuhai]]. In the team's debut at the [[2007 24 Hours of Le Mans|24 Hours of Le Mans]], their C6.R was able to finish, but in a distant 28th place. |
| The 396-cubic-inch (6.5 L) V8 was introduced in the 1965 Corvette as the L78 option and in the Z16 Chevelle. It had a bore of 4.094 in and stroke of 3.76 in (104 mm by 96 mm), and produced 425 hp (317 kW) and 415 ft·lbf (563 N·m). This version of the 396 was equipped with four bolt main bearing caps and was very comfortable with being operated in the upper 6000 rpm range.
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| Introduced in 1970, the 402-cubic-inch (6.6 L) was a 396-cubic-inch bored out by 0.030 in (0.8 mm). Despite the fact that it was {{convert|6|CID|cc}} larger, Chevy continued marketing it under the popular "396" label in the smaller models, and as the "Turbo-Jet 400" in the full-size series.
| | ====Luc Alphand Aventures==== |
| | [[Image:Luc Alphand Corvette 72.jpg|thumb|right|Luc Alphand's #72 C6.R, winner of the GT1 class Drivers and Teams Championships in the [[2008 Le Mans Series season]]]] |
| | Another team who had already purchased a C5-R previously, [[Luc Alphand]]'s squad purchased a C6.R to run alongside their C5-R in the [[Le Mans Series]] as the team earned factory support from Pratt & Miller for their European campaign. The car began the year with a victory at the [[2007 1000km of Monza|1000 km of Monza]] before following it with a second at the [[2007 1000km of Nürburgring|1000 km of Nürburgring]] and earning them second in their class championship. The team's two cars were also entered in the 24 Hours of Le Mans, with the C6.R earning a 12th place finish and 7th in GT1. |
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| '''Power rating(s) by year:''' | | As part of Pratt & Miller's support of Luc Alphand, Corvette Racing drivers [[Oliver Gavin]] and [[Olivier Beretta]] were entered in Luc Alphand's C6.R for the Spa 24 Hours. The team managed to finish in sixth place. |
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| * 1965: {{convert|375|hp|abbr=on}}
| | ==Pratt & Miller C6RS== |
| * 1966: {{convert|325|hp|abbr=on}}/{{convert|350|hp|abbr=on}}/{{convert|360|hp|abbr=on}}/{{convert|375|hp|abbr=on}}
| | It is a conversion of Corvette Z06 that resembles C6.R and shares components with the race car, produced by Pratt & Miller. It uses [[Katech Performance]] 8.2L engine rated 600 horsepower and 600 lb-ft torque. The car has top speed of 202mph.<ref>[http://www.prattmillerc6rs.com/202.htm PRATT & MILLER CORVETTE C6RS Tops 200 mph in Speed Test]</ref> The production began on April 2008.<ref>[http://www.prattmillerc6rs.com/pressrelease.htm Pratt & Miller Engineering Introduces Corvette C6RS Supercar for the Street]</ref> 25 were produced in the first year.<ref>[http://www.edmunds.com/insideline/do/News/articleId=123323 Pratt & Miller To Build Just 25 Corvette C6RS Supercars in 2008]</ref> |
| * 1967: {{convert|325|hp|abbr=on}}/{{convert|350|hp|abbr=on}}/{{convert|375|hp|abbr=on}}
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| * 1968: {{convert|325|hp|abbr=on}}/{{convert|350|hp|abbr=on}}/{{convert|375|hp|abbr=on}}
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| * 1969: {{convert|265|hp|abbr=on}}(2bbl)/{{convert|325|hp|abbr=on}}/{{convert|350|hp|abbr=on}}/{{convert|375|hp|abbr=on}}
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| * 1970: {{convert|330|hp|abbr=on}}/{{convert|350|hp|abbr=on}}/{{convert|375|hp|abbr=on}}
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| * 1971: {{convert|300|hp|abbr=on}}
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| * 1972: {{convert|240|hp|abbr=on}}
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| '''Used in:'''
| | A version running E85 ethanol was created with [[Jay Leno]], appeared in 2007 SEMA show.<ref>[http://www.autobloggreen.com/2007/10/29/sema-2007-jay-lenos-new-e85-c6rs-corvette/ SEMA 2007: Jay Leno's new E85 C6RS Corvette]</ref> |
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| * 1965 [[Chevrolet Corvette]]
| | Convertible version was unveiled in 2008 [[12 Hours of Sebring]].<ref>[http://www.prattmillerc6rs.com/c6rs_sebring.htm Pratt & Miller To Unveil Convertible C6RS Supercar At Sebring 12-Hour Race]</ref> |
| * 1965–1972 [[Chevrolet Chevelle]]
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| * 1967–1972 [[Chevrolet Camaro]]
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| * 1968–1970 [[Chevrolet Nova]]
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| * 1970–1972 [[Chevrolet Monte Carlo]]
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| * 1965–1972 [[Chevrolet Biscayne]], [[Chevrolet Bel Air]], [[Chevrolet Impala]], [[Chevrolet Impala|Chevrolet Impala SS]], [[Chevrolet Caprice]]
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| ===427=== | | ==Future Development== |
| {| border=0 align=right
| | On September 9th, 2008 Corvette Racing GM Road Racing Group manager Steve Wesoloski and Corvette Racing program manager Doug Fehan announced that for the 2009 ALMS season they would be running the C6.R in the GT1 class for only the first half of the season. After the 24 hours of Le Mans, Corvette Racing will be running a newly designed C6.R in the GT2 class in preparation for the 2010 season's newly designed GT class regulations. |
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| |[[Image:1966 Chevrolet Corvette 427 engine.JPG|thumb|150px|L36 427 in a 1966 [[Chevrolet Corvette]]]]
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| |[[Image:SC06 1967 Chevrolet Corvette 427 L89 engine.jpg|thumb|150px|L71 427 in a 1967 [[Chevrolet Corvette]]]]
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| The highly successful and versatile 427 cubic inch (7.0 L) version of the Mark IV engine was introduced in 1966 as a production engine option for full sized Chevrolets and Corvettes. The bore was increased to {{convert|4.25|in|mm}}, with power ratings varying widely depending on the application. There were smooth running versions with [[hydraulic lifters]] suitable for powering the family [[station wagon]], as well as rough idling, high-revving solid lifter models that resembled racing powerplants.
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| Not every version of the 427 was available in every car, and ordering the highest performance versions often required that other options be added to or deleted from the car (for example, power steering wasn't available with the high performance models). This relationship between engine configuration and vehicle options often resulted in what was jokingly referred to as a "racing [[taxicab]]," the description usually applied to a minimally equipped, plain looking, two door [[Chevrolet Biscayne|Biscayne]] [[sedan (car)|sedan]] fitted with the {{convert|425|hp}} version of the 427— (RPO L72), resulting in a vehicle whose performance was the polar opposite of a taxi. This lightweight, big-block Biscayne was also commonly referred to as "Bisquick."
| | ==References== |
| | | {{reflist}} |
| Perhaps the ultimate 427 for street applications was the {{convert|435|hp}} L71 version available in 1967 to 1969 Corvettes, and in the Italian [[Iso Grifo]]. This engine was identical to the {{convert|425|hp|abbr=on}} L72 427 (first introduced in 1966) but was fitted with three two barrel carburetors in lieu of the L72's single 4 barrel. Both engines utilized the same high lift, long duration, high overlap camshaft and large port, cast iron heads in order to maximum cylinder head flow (and, hence, engine power) at elevated engine operating speeds. Consequently, the engines offered very similar performance and resulted in a car whose performance was described by one automotive journalist as "the ultimate in sheer neck-snapping overkill." Typical magazine road tests of the day yielded sub-6 second zero to {{convert|60|mi/h|km/h}} times and quarter miles in the mid 13 second/106 MPH range for both the L72 and L71.
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| RPO L89 was an L71 fitted with aluminum heads (often dealer installed). While this option produced no power advantage, it did reduce engine (and hence, vehicle) weight by roughly {{convert|75|lb}}. This resulted in superior vehicle weight distribution for improved handling, although any difference in straight line performance was essentially negligible.
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| The most legendary version of the 427 was undoubtedly the 1969 ZL1 engine. It was developed primarily for [[Can-Am]] racing, where it was very successful in cars like the Chaparrel 2F and McLaren M8B. The ZL1 had specifications nearly identical to the production L88 version of the 427, but featured an all-aluminum cylinder block in addition to aluminum cylinder heads, which dropped total engine weight into small block Chevy territory (approx. {{convert|575|lb|kg|abbr=on|disp=s}} dressed). The engine was also fitted with the new open combustion chamber cylinder heads, a light weight aluminum water pump, a camshaft that was slightly "hotter" than the L88's and a specially tuned aluminum intake manifold. Like the L88, the ZL1 required 103 octane RON (minimum) fuel, which made both engines largely unsuitable for street use in an era where 102 octane RON (Sunoco 260) represented the highest octane gasoline sold at common retail stations. Impressive as the ZL1 was in its day and despite the "larger than life legends" surrounding it, actual engine dyno tests of a certified production line stock ZL1 revealed 376 SAE net HP, with output swelling to 524 Gross HP with the help of optimal carb. and ignition tuning, open long tube racing headers and with no power sapping engine accessories or air cleaner in place. [http://www.camaros.org/copo.shtml ZL1 DYNO TEST - COPO CAMARO WEBSITE] A second engine dyno test conducted on a second production line stock (but recently rebuilt and partially blueprinted) ZL1 revealed nearly identical figures for the various "Gross" conditions. [http://members.cox.net/harddrivin1le/ZL1DYNOTEST.JPG 2nd ZL1 DYNO TEST] Magazine tests of the ZL1 were quite rare due to the rarity of the engine itself. "High Performance Cars" tested a production line stock version and recorded a 13.1 second/110 MPH quarter mile, which correlates quite well with the previously referenced 376 Net HP figure. "Super Stock and Drag Racing Magazine" recorded an 11.62 second/122.15 MPH quarter mile in a ZL1 Camaro that was professionally tuned and driven by drag racing legend Dick Harrell, although that car was equipped with open long tube S&S equal length headers, drag slicks and minor suspension modifications. The 122.15 MPH trap speed indicated very low 11 second ET potential (e.g. with larger drag slicks) and suggested something on the order of 495 "as installed" HP in that modified configuration. This large difference in power suggests that the OEM exhaust manifolds and exhaust system were very restrictive in the ZL1 application, as was also the case with the similar L88.
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| The race-prepped ZL1s that were utilized in Can-Am racing were capable of developing something on the order of 600 "as raced" HP as the result of complete engine blueprinting, fuel injection, more aggressive cam-shaft grinds, custom fabricated, power optimizing long tube racing headers, dry sump lubrication and various other power and durability enhancing changes. It is this figure that is often erroneously cited as the "actual" output of production line stock ZL1 passenger car engines (e.g. 1969 COPO 9560 Camaro).
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| The 4718 [[USD|dollar]] cost of the ZL1 option doubled the price of the 1969 Corvette, but resulted in a car with exceptional performance for its day. Just two production Corvettes (factory option at dealer) and 69 Camaros (non-dealer option from factory - COPO 9560) were built with the ZL1.
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| Chevrolet capitalized on the versatility of the 427 design by producing a wide variety of high performance, "over the counter" engine components (marketed as "heavy duty" or "extra capacity" components to mask their intended racing application), as well as ready-to-race "replacement" engines in shipping crates. Some of the components were developed to enhance the engine's reliability during high RPM operation, possibly justifying the use of the description "heavy duty." However, most of these items were racing parts originally designed for Can-Am competition that found their way on to dealers' shelves, and were meant to boost the engine's already impressive power output. As a result of this activity, the 427 quickly became dominant in [[drag racing]].
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| Beginning in 1969, the highest performance 427 models were fitted with the new open (vs. closed) chamber cylinder head, s which along with design improvements in crankshafts, connecting rods and pistons adopted from the Can-Am development program, resulted in an engine with substantially increased performance and reliability. This development culminated in a specialty version of the engine called the ZLX, which was essentially a ZL1 engine built with the L88 engine's sturdy, four bolt main bearing iron block (it has been suggested that "ZLX" was a code name for ZL1 crossover). The ZLX, available as a short block assembly or complete "replacement" engine in the crate from a few dealers, was a resounding success and became a best-seller by [[aftermarket (automotive)|after market racing components]] standards—the closest thing to an all-out competition engine ever offered to the general public.
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| Chevrolet gave all 427 engines except the ZL1 a torque rating of 460 ft·lbf (624 N·m).
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| {| class="wikitable"
| |
| !First<br>Year
| |
| !Last<br>Year
| |
| !Engine<br>Code
| |
| !Features
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| !Compression<br>ratio
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| !Factory<br>Gross Power<br>Rating
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| |-
| |
| |1966||1969|| L36 || 4-barrel || 10.25:1 || 390 hp (291 kW)
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| |-
| |
| |1966||1966|| L72 || 4-barrel + solid-lifters, more aggressive cam and high flow cylinder heads|| |11.00:1 || 425 hp (317 kW)<ref>Chevrolet actually advertised this engine as 450 hp (336 kW) for a short period of time. There is speculation over whether this engine actually put out 450 Gross HP, or if this was a marketing oversight that was later corrected.</ref>
| |
| |-
| |
| |1967||1969|| L68 || L36 with 3x2-barrel carbs. || 10.25:1 || 400 hp (298 kW)
| |
| |-
| |
| |1967||1969|| L71 || L72 with 3X2 barrel carbs.|| 11.00:1 || 435 hp (324 kW)
| |
| |-
| |
| |1967||1969|| L89 || L71 + aluminum heads; RPO L89 also applied to L78 "375 HP" 396 engine with aluminum head option. || 11.00:1 || 435 hp (324 kW)
| |
| |-
| |
| |1967||1969|| L88 || Racing-spec cam, high-flow aluminum heads (casting #s varied by model year) and some upgraded, competition-grade parts || 12.50:1<ref>L88 had a 12.5:1 compression ratio with closed chamber heads except during the last half of 1969, when it had open chambered heads that yielded 12.0:1</ref> || 430 hp (321 kW)<ref>L88 was rated for {{convert|430|hp|abbr=on}} at 5200 rpm. With stock exhaust manifolds and operation in the 6,800 rpm range, it was generally accepted that the engine was capable of producing in excess of 500 Gross HP with free-flowing (open) long tube headers.</ref>
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| |-
| |
| |1969||1969|| ZL1 || Aluminum block with open chamber "3946074" aluminum heads; cam even "hotter" than L88's; upgraded parts similar to L88's || 12.00:1 || 430 hp (321 kW)
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| |-
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| |-
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| |1970||1977(?)|| ZLX || L88-ZL1 hybrid; iron block with aluminum heads || 12.25:1 || 430(?) hp (321 kW)
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| |-
| |
| |}Notes: <references/>
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| | |
| * 1966–1969 [[Chevrolet Biscayne]]
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| * 1966–1969 [[Chevrolet Caprice]]
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| * 1966–1969 [[Chevrolet Impala]]
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| * 1966–1969 [[Chevrolet Corvette]]
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| * 1968–1969 [[Chevrolet Camaro]] (most were dealer installed, but in 1969 both the L-72 and the ZL-1 were factory options)
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| ===454=== | |
| The big-block was expanded again for 1970 to 454 cubic inches (7.4 L) with a 4.251 in (108 mm) bore and 4 in (102 mm) stroke. The 1970 [[Chevy Corvette]] LS5 version of this engine produced {{Convert|390|hp|kW|0|abbr=on}} and 500 ft·lbf (678 N·m), and the LS6 engine was rated at 450 hp (336 kW). It has been suggested that the LS6 was substantially underrated and actually produced well over {{convert|500|hp}} as delivered from the factory, although there is no empirical evidence to support this claim. Indeed, the AHRA ASA Class record holding Chevelle LS6 for the 1970 season posted a record setting trap speed of {{convert|106.76|mi/h|km/h|abbr=on}} [http://www.chevelle454ls6.com/1970_chevelle_454_ls6.htm "1970 ASA LS6 454 Records"], which suggests something on the order of 370 "as installed" (SAE Net) HP for a {{convert|3900|lb}} car and driver combination.
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| A 465 hp (347 kW) and 490 lb·ft (664 N·m) version of the 454, dubbed LS7 was also designed but never went to production. However, a handful of LS7 intake manifolds were produced and sold by a handful of Chevy dealers as performance parts. The LS7 was later offered as a crate engine from GM and advertised at {{convert|500|hp|abbr=on}}.
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| Power began falling off after 1970, with the 1971 LS5 producing 365 hp (272 kW) and 465 lb·ft (630 N·m), and the LS6 option coming in at 425 hp (317 kW) and 475 lb·ft (644 N·m). Only the LS5 remained in 1972, when SAE net power ratings and the move towards emission compliance resulted in to 270 hp (201 kW) and 390 lb·ft (529 N·m). The 1973 LS4 produced 275 hp (205 kW) and 390 lb·ft (529 N·m), with 5 hp (4 kW) and 10 lb·ft (14 N·m) gone the following year. Hardened valve seats helped allow these engines to last much longer than the earlier versions, even without the protection previously provided by lead from fuel. 1974 was the last year of the 454 in the Corvette though the Chevelle offered it in the first 1/2 of the 1975 model year. It was also available in the full size Impala/Caprice until model year 1976.
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| GM continued to use the 7.4 L (454 cu in) in their truck line, introducing a new [[GM Vortec engine#7400|Vortec 7400]] version in 1996.
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| GM also introduced the 7.4 L 454 EFI in 1990 (known as the GEN V; the previous generation was known as the Mark IV produced between 1965-90; the GEN prefix was used since [[Ford Motor Company]] owns the Mark V naming rights since it was used on a [[Lincoln (automobile)|Lincoln]] automobile between 1977-79), which was electronically fuel injected giving more power and torque. Instead of the regular {{convert|290|hp|abbr=on}}, the 454 EFI version cranked out {{convert|365|hp|abbr=on}} and {{convert|415|lb.ft|abbr=on}} of torque. The 454 EFI power ratings were very similar to the early 1970s LS5 454, which was found in early 1970s corvettes and chevelles.
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| The 7.4 L 454 EFI was found on GM 3500 trucks throughout the early 1990s until replaced with the Vortec 7400 (GEN VI) in 1996.
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| * 1970–1976 [[Chevrolet|Chevrolet Cars]]
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| * 1970–1974 [[Chevrolet Corvette]]
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| ===502===
| |
| [[File:Chevy502CID.jpg|thumb|right|200px|The Chevy 502 V8]]The {{convert|502|CID|L|1|adj=on}} was offered in various fleet and service vehicles in the late 80's and early 90's {{Fact|date=May 2008}}. It had a bore of 4.466 with a stroke of 4.00 and was a [[cast iron]] 4-bolt main block. Later GM offered it in their Performance Parts catalog, available as multiple [[crate motor]]s with horse power ratings between {{Convert|338|hp|kW|0|abbr=on}} to {{Convert|502|hp|kW|0|abbr=on}}, and torque of {{auto ftlbf|470}} to {{auto ftlbf|567}} in "Base" and "Deluxe" packages.<ref>[http://www.gmperformanceparts.com/_res/pdf/CrateEngineQRC2008.pdf 2008 Crate Engine Catalog (p.25)]</ref> The "Ram Jet 502"<ref>[http://www.gmperformanceparts.com/EngineShowcase/index.jsp?engId=RamJet502&engine=Ram%20Jet%20502&sku=12499121&engCat=bb Ram Jet 502 overview]</ref> ({{Convert|502|hp|kW|0|abbr=on}} / {{auto ftlbf|565}}) crate motor was offered with [[fuel injection]], and came as a [[turn key]] setup which includes all the wiring and electronics needed to operate in any vehicle.
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| ===572===
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| Chevrolet began offering an {{convert|572|CID|L|1|adj=on}} "crate motor" in 2003 which produced {{Convert|720|hp|kW|0|abbr=on}} and {{auto ftlbf|685}} of torque,<ref>[http://www.gmperformanceparts.com/EngineShowcase/tech_specs.jsp?engId=ZZ572720&engine=ZZ%20572%20720&sku=12498827&engCat=bb ZZ 572/720R specifications]</ref> and more recently a {{Convert|620|hp|kW|0|abbr=on}} / {{auto ftlbf|650}} version capable of running on 93 octane street gasoline.<ref>[http://www.gmperformanceparts.com/EngineShowcase/tech_specs.jsp?engId=ZZ572620&engine=ZZ%20572/620&sku=12498793&engCat=bb ZZ 572/620 specifications]</ref>
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| ===The aftermarket===
| |
| The large variety of aftermarket components manufactured for the big block family makes it possible to build a complete big block engine that contains no Chevrolet components. Blocks made of both iron and aluminum alloys are available in stock configurations and also with increased deck height to allow longer stroke or more favorable rod length ratios, providing the ability to make {{convert|632|CID|L|1|adj=on}} engines, and larger.
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| | |
| ===Commercial applications===
| |
| Mark IV engines saw extensive application in Chevrolet and GMC medium duty trucks, as well as in [[Blue Bird Corporation]] All American and TC/2000 transit buses (the latter up until 1995, using a purpose-built, carbureted 427). In addition to the 427, a 366-[[cubic inch]] (6.0 [[liter]]) version was produced for the commercial market. Both the 366 and 427 commercial versions were built with a raised deck, four bolt main bearing cap cylinder block to accommodate an extra oil control ring on the pistons. Unfortunately, the raised deck design complicated the use of the block in racing applications, as standard intake manifolds required spacers for proper fit. Distributors with adjustable collars that allowed adjustments to the length of the distributor shaft also had to be used with 366 and 427 truck blocks.
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| Mark IV engines also found themselves widely used in power boats, a natural application for these robust power plants. Many of these engines were ordinary Chevrolet production models that were fitted with the necessary accessories and drive system to adapt them to marine propulsion. [[Mercury Marine]], in particular, was a major user of the Mark IV in marine drives, and relabeled the engines with their corporate logo.
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| | |
| ==8100==
| |
| The [[GM Vortec engine#8100|Vortec 8100]] 7th generation (known as gen VII) Chevrolet big block, has the same bore as a 454 (4.25 inches), but has a stroke of {{convert|4.37|in|mm}}. It is similar to the smaller [[GM LS engine]] family in that it has coil-on-plug ignition and a 1-8-7-2-6-5-4-3 firing order. It was used in 3/4 ton and larger light trucks, and medium duty commercial vehicles. http://en.wikipedia.org/wiki/GM_Vortec_engine#8100
| |
| Produced in the years of 2001–2006.5.
| |
| | |
| ==See also==
| |
| From the 1950s through the 1970s, each GM division had its own V8 engine family. Many were shared among other divisions, but each design is most-closely associated with its own division:
| |
| * [[Buick V8 engine]]
| |
| * [[Cadillac V8 engine]]
| |
| * [[Chevrolet Small-Block engine]]
| |
| * [[Oldsmobile V8 engine]]
| |
| * [[Pontiac V8 engine]]
| |
|
| |
|
| GM later standardized on the later generations of the Chevrolet design:
| | ==External links== |
| * [[GM LT engine]]—Generation II small-block
| |
| * [[GM LS engine]]—Generation III/IV small-block
| |
| * [[List of GM engines]]
| |
|
| |
|
| == Notes ==
| | *[http://www.racecar-engineering.com/articles/sportscar/258133/corvette-c6r.html C6R Technical Review] |
| <references/>
| | *[http://www.corvettemotorsport.com Corvette Racing Europe] |
| | | *[http://palmeter.com/C6RChasSNHist.htm C6.R Chassis History] |
| ==References==
| | *[http://www.corvetteracing.com/ Corvette Racing] |
| *{{cite book | author=Peter C Sessler | title=Ultimate American V8 Engine Data Book | publisher=MotorBooks/MBI Publishing Company | year=1999 | isbn=0-7603-0489-0}} | | *[http://www.prattmillerc6rs.com/ Pratt & Miller C6RS] |
| | *[http://www.psi-motorsport.com/racing/index.php PSI Motorsport] |
| | *[http://www.luc-alphand.com/courses/ Luc Alphand Aventures] (French) |
|
| |
|
| [[Category:Chevrolet engines|Big-Block]]
| | {{Corvette timeline}} |
|
| |
|
| [[sv:Chevrolet Big block]] | | [[Category:Chevrolet Corvette|C6.R]] |
| | [[Category:Grand tourer racing cars]] |
One of Corvette Racing's C6.Rs, driven by Jan Magnussen and Johnny O'Connell.
The Chevrolet Corvette C6.R is a grand tourer racing car built by Pratt & Miller and General Motors for competition in endurance racing. It is a replacement for the Corvette C5-R racing car, applying the body style of the new C6 generation Chevrolet Corvette as well as improvements to increase the speed and reliability on the track. Since its debut in 2005, it has continued on from the previous dominance of the C5-R in its racing class with multiple American Le Mans Series championships and race wins in the Le Mans Series, FIA GT Championship, and 24 Hours of Le Mans.
Development
Having already established the C5-R as a winning car, the development of the C6.R was more of an evolution of a design rather than an all new car which required long periods of testing and design. Pratt & Miller's process was aided by the fact that, unlike the C5-R which debuted several years after the C5 generation Corvette was on the streets, the C6.R and C6 generation Corvettes would be developed at the same time. This meant that design elements which would help the race car could be adapted to the road car, allowing the C6.R to use more exotic design features but still meet homologation requirements. In turn, this meant racing elements could be adapted to the Corvette Z06 performance car, which the C6.R shares it exterior styling with.
A rear-view of a C6.R, showing the air conditioner exhaust fan located in the center of the bodywork.
Much of the framework of the road legal C6 was retained on the C6.R, leading to increased use of weight-saving aluminium. The road car would also replace the C5's pop-up headlights with permanent designs integrated into the bodywork. This meant that the racing car would have better air flow over the front of the car, doing away with their replacements for the pop-up headlights which stuck out of the bodywork. The large grill opening on the car would also serve to eliminate the variety of openings on the C5-R to feed not only the brake cooling ducts, but also help with downforce by exiting back out the top of the bonnet.
Underneath, the C6.R retained much of the mechanical elements from the C5-R. The same Katech-built 7.0 litre V8 was used, but more closely based on the LS7 from the Z06. This engine, known as the LS7.R, would go on to earn the Global Motorsports Engine of the Year award in 2006 for its performance and endurance capabilities. Like the C5-R, the C6.R lacked a rear window due to structural framework and fuel tanks taking up the space behind the cockpit. However, an innovation on the C6.R was the addition of a small video camera into the rear bumper, and a monitor placed on the roof of the cockpit. This allowed the drivers a better view behind them, instead of having to rely on their side mirrors.
Another innovation was the use of an air conditioning system in the car in order to help drivers better endure high cockpit temperatures. This required the addition of a large suction fan to the rear of the car, as well as intakes integrated into the side mirrors. One innovation which the C6.R debuted in 2007 was the use of variable displacement. This system would disable half of the cylinders in the engine during caution periods in order to increase fuel economy when speed was not important. Although the system was tested during the season, its failure at the 2007 24 Hours of Le Mans led the team to remove it from the cars until it could be further evaluated.
As of the end of the 2007 season, six C6.Rs had been built by Pratt & Miller. A seventh car, used for development work, was actually built on a C5-R chassis but adapted to carry C6.R bodywork. This car has never raced and is used merely as a show car, making its public debut alongside the C6 Corvette at the 2005 North American International Auto Show.
Racing history
Corvette Racing
A C6.R driving down the pit lane during the 2005 24 Hours of Le Mans.
The C6.R in 2008, now running E85 ethanol fuel.
Following the retirement of the C5-R at the end of 2004, the factory Corvette Racing squad started 2005 with two brand new C6.Rs. Unlike the previous car, which had only ran select events until it could be proven quick and reliable, the C6.Rs would compete in the full American Le Mans Series season in their first year. The season did not begin as Corvette Racing had planned however, as the equally new Prodrive Aston Martin DBR9 managed to win the event, earning Corvette Racing their first loss since the end of 2003. Prodrive returned to Europe after Sebring, and Corvette Racing was able to earn wins in each of the succeeding races that season. Even when Prodrive returned for the final two rounds, the improved Corvettes continued their streak and won both races. The C6.Rs also ventured to Europe for the 24 Hours of Le Mans, where the team were able to outlast the quicker DBR9s to earn a 1-2 victory and finish fifth and sixth overall.
In 2006, Prodrive chose to concentrate on the American Le Mans Series, giving Corvette Racing a battle throughout the season. Corvette Racing avenged their loss at Sebring, but Aston Martin managed their own victories later in the season. The two teams were close in the points championship throughout the season, before Corvette Racing managed to earn a three-point margin in the last race and won their second straight championship. At Le Mans, the Aston Martins once again faltered with reliability problems after leading the event, allowing a Corvette C6.R to finish the race fourth overall and win the GT1 class.
Following the 2006 season, Prodrive returned to Europe to concentrate on improving the DBR9 for Le Mans. This meant that Corvette Racing was left without a major opponent in the American Le Mans Series, and in fact were the only competitors in the GT1 class for nine out of twelve races that year, and easily allowing Corvette Racing to earn their third championship. At Le Mans, the Corvettes were not able to repeat their previous success as Aston Martin was finally able to reliably maintain their pace over 24 hours and earn their first class victory, leaving Corvette Racing with second.
In order to honor Canadian driver Ron Fellows, Corvette Racing entered a third C6.R at the Grand Prix of Mosport. This third car was painted in white and red colors to match the Ron Fellows Edition Corvette Z06, a limited edition road car in honor of Fellows's involvement with the Corvette Racing program since its inception. Ron Fellows drove the car for his home race.
Corvette Racing plans to continue to run the C6.Rs in the American Le Mans Series and at the 24 Hours of Le Mans in 2008.
Privateer teams
Like the C5-R, C6.Rs which had been used by the factory team eventually ended up in the hands of privateers once they were replaced by newer chassis. Unlike before, these Corvettes were sold less then a year after they had debuted, rather than the four years it took for a C5-R to be sold to another team.
GLPK-Carsport
GLPK-Carsport's C6.R running in the 2006 FIA GT Dubai 500km.
Buying one of the two C6.Rs used by Corvette Racing during the 2005 season, GLPK-Carsport added this chassis to their stable to replace their C5-R in the FIA GT Championship. The driving team of Bert Longin, Anthony Kumpen, and Mike Hezemans drove the car throughout the season, and were able to score a victory at Paul Ricard as well as a third place finish at the Spa 24 Hours. The team eventually ended the season in fifth place in the championship.
For 2007, GLPK Carsport was split into Carsport Holland and PK-Carsport. PK-Carsport returned to running the C5-R they ran in Belcar to FIA GT, while Carsport Holland took over the C6.R.
Carsport Holland
Continuing where the former GLPK-Carsport had left off, Carsport Holland's Mike Hezemans and partner Phoenix Racing's Jean-Denis Délétraz improved on the C6.R's position the previous season.
Carsport Holland won the Spa 24 Hours. Joined by Marcel Fässler and Fabrizio Gollin, the team was able to fend off the Vitaphone Racing Maserati and earn Corvette's first victory at the endurance event. Carsport Holland earned one final victory at Nogaro before closing the season fourth in the teams' championship and third in the drivers' championship.
PSI Experience
At the same time that GLPK-Carsport purchased an ex-factory C6.R, PSI Experience also bought a C6.R to add alongside their C5-R. PSI Experience chose to concentrate their efforts on the French FFSA GT Championship as well as joining the Le Mans Series. The team earned one victory at Lédenon for FFSA, while a third at the 1000 km of Spa was their best result in the LMS. PSI also chose to enter a few FIA GT rounds, most notably the Spa 24 Hours. The team finished fifth in the event, before joining FIA GT once again at Paul Ricard and finishing second behind GLPK-Carsport's C6.R.
For 2007, PSI's C6.R was entered mostly in FFSA GT events, while select appearances in FIA GT as well as the 24 Hours of Le Mans were made. PSI once again managed a sole win in FFSA, winning at the final round at Magny-Cours. Their best FIA GT result was a second place at the season opener in Zhuhai. In the team's debut at the 24 Hours of Le Mans, their C6.R was able to finish, but in a distant 28th place.
Luc Alphand Aventures
Luc Alphand's #72 C6.R, winner of the GT1 class Drivers and Teams Championships in the 2008 Le Mans Series season
Another team who had already purchased a C5-R previously, Luc Alphand's squad purchased a C6.R to run alongside their C5-R in the Le Mans Series as the team earned factory support from Pratt & Miller for their European campaign. The car began the year with a victory at the 1000 km of Monza before following it with a second at the 1000 km of Nürburgring and earning them second in their class championship. The team's two cars were also entered in the 24 Hours of Le Mans, with the C6.R earning a 12th place finish and 7th in GT1.
As part of Pratt & Miller's support of Luc Alphand, Corvette Racing drivers Oliver Gavin and Olivier Beretta were entered in Luc Alphand's C6.R for the Spa 24 Hours. The team managed to finish in sixth place.
Pratt & Miller C6RS
It is a conversion of Corvette Z06 that resembles C6.R and shares components with the race car, produced by Pratt & Miller. It uses Katech Performance 8.2L engine rated 600 horsepower and 600 lb-ft torque. The car has top speed of 202mph.[1] The production began on April 2008.[2] 25 were produced in the first year.[3]
A version running E85 ethanol was created with Jay Leno, appeared in 2007 SEMA show.[4]
Convertible version was unveiled in 2008 12 Hours of Sebring.[5]
Future Development
On September 9th, 2008 Corvette Racing GM Road Racing Group manager Steve Wesoloski and Corvette Racing program manager Doug Fehan announced that for the 2009 ALMS season they would be running the C6.R in the GT1 class for only the first half of the season. After the 24 hours of Le Mans, Corvette Racing will be running a newly designed C6.R in the GT2 class in preparation for the 2010 season's newly designed GT class regulations.
References
External links
