Why No C6 Corvette in NASCAR Races?
Now that is funny.
07-30-2009, 05:46 AM
#83
Le Mans Master
Restrictor plate engines run at those tracks and make about 450 hp max and can't pull high rpm as the areo drag on those Cot bodies are close to a brick in aero.
also the cot doesn't excede 1.2 G at any track. The last Radical I owned was pulling 3.1 g in lateral and 2.5 g in braking. Nascar is so OLD SCHOOL . My Radical was (on the dyno at the rear wheels) making 275 hp out of 70 cubic inches with rpm at 9500 to 11500 rpm for all races and lasted the full season.This is in an 1100 lb car. Nascar engines are used for just one race and at 358 inches and 800-850 hp in a 3400+ lb car. Does the word TAXI help when you think of Nascar.
also the cot doesn't excede 1.2 G at any track. The last Radical I owned was pulling 3.1 g in lateral and 2.5 g in braking. Nascar is so OLD SCHOOL . My Radical was (on the dyno at the rear wheels) making 275 hp out of 70 cubic inches with rpm at 9500 to 11500 rpm for all races and lasted the full season.This is in an 1100 lb car. Nascar engines are used for just one race and at 358 inches and 800-850 hp in a 3400+ lb car. Does the word TAXI help when you think of Nascar.
I think maybe you're somewhat disgusted with all the attention NASCAR gets while most of us have never heard of a radical before. Must be because it doesn't get the attention or support that NASCAR does huh?
U.M.
07-30-2009, 06:38 AM
#84
Le Mans Master
Boy someone has a very big chip on their shoulder about NASCAR...
I think maybe you're somewhat disgusted with all the attention NASCAR gets while most of us have never heard of a radical before. Must be because it doesn't get the attention or support that NASCAR does huh?
U.M.
I think maybe you're somewhat disgusted with all the attention NASCAR gets while most of us have never heard of a radical before. Must be because it doesn't get the attention or support that NASCAR does huh?
U.M.
07-30-2009, 07:43 AM
#85
Sir, I have raced both... Nascar (nascrap) cars are not fast on a road course. Ever wonder why they run a short course at Walkins Glen and Sears Point? It so you can't easily compare lap times to real race cars on the full course, which is what most race on.. Blah Blah Blah,,, 800 horse power. My 45 year old wife in a 115 horsepower Formula ford turned lap times that would have put her 4th on the cup grid that day. Even Nascar Daytona Prototypes are slow, and at VIR are 2 seconds slower than an SCCA one liter sports racer. ONE liter,, that is a 62 cubic inch engine. A good GT1 SCCA corvette would walk away from any Nascar Whatever they call them this year.. Oh yeah,, Car of the future,,,,Solid rear axle,, carb,, 10 inch wide wheels, 3400 lbs, Its not racing, its moving billboards, speed doesn't matter, all the sponsors must get equal time, so all the cars must be the same.
The Corvette does race at a higher level. Racing Rant over
The Corvette does race at a higher level. Racing Rant over
back in the day, when they raced cars that you could actually buy versions of, it was cool, today what they race has no relevance to what you can buy.. what is it called 'stock car racing'? STOCK? no way no how...
its a bunch of almost exactly the same purpose made oval boxes going around and around and around and around and around and around and around and around and around and around and around and around and around...
bring back the moonshiners and their modified STOCK cars.. lets see em race what you can buy...
07-30-2009, 09:19 AM
#89
Melting Slicks
Restrictor plate engines run at those tracks and make about 450 hp max and can't pull high rpm as the areo drag on those Cot bodies are close to a brick in aero.
also the cot doesn't excede 1.2 G at any track. The last Radical I owned was pulling 3.1 g in lateral and 2.5 g in braking. Nascar is so OLD SCHOOL . My Radical was (on the dyno at the rear wheels) making 275 hp out of 70 cubic inches with rpm at 9500 to 11500 rpm for all races and lasted the full season.This is in an 1100 lb car. Nascar engines are used for just one race and at 358 inches and 800-850 hp in a 3400+ lb car. Does the word TAXI help when you think of Nascar.
also the cot doesn't excede 1.2 G at any track. The last Radical I owned was pulling 3.1 g in lateral and 2.5 g in braking. Nascar is so OLD SCHOOL . My Radical was (on the dyno at the rear wheels) making 275 hp out of 70 cubic inches with rpm at 9500 to 11500 rpm for all races and lasted the full season.This is in an 1100 lb car. Nascar engines are used for just one race and at 358 inches and 800-850 hp in a 3400+ lb car. Does the word TAXI help when you think of Nascar.
They're 3400 pound sedans with old-tech pushrod V8s that make 850 hp and run as fast as 205 mph 3-wide, sometimes TOUCHING the car in front of, behind and/or next to them.
On every track except for the 'plate tracks, they are right on the ragged edge of a 4-wheel drift exiting every single turn for 500 miles.
On the plate tracks, there are usually positional swings of up to 15 spots in seconds....the top half of the field usually finishes the race within 2 seconds of eachother at 200 mph.
The engines turn well over 9000 RPM which is astronomical for a "stone-age" 358 small block.
Why everyone makes fun of NASCAR is beyond me....It's a classic case of "if it ai'nt broke, don't fix it". Why is it important that Cup cars aren't rolling computers that have 87 different driver aids? It's a simply formula......V8, rear-drive, 4-speed stick, driver, Shut up and race....
07-30-2009, 09:38 AM
#90
I fail to see a point to this post....it sounds like your trying to make fun of NASCAR COTs because they're different than your "radical" go-kart thing. Why is different bad?
They're 3400 pound sedans with old-tech pushrod V8s that make 850 hp and run as fast as 205 mph 3-wide, sometimes TOUCHING the car in front of, behind and/or next to them.
On every track except for the 'plate tracks, they are right on the ragged edge of a 4-wheel drift exiting every single turn for 500 miles.
On the plate tracks, there are usually positional swings of up to 15 spots in seconds....the top half of the field usually finishes the race within 2 seconds of eachother at 200 mph.
The engines turn well over 9000 RPM which is astronomical for a "stone-age" 358 small block.
Why everyone makes fun of NASCAR is beyond me....It's a classic case of "if it ai'nt broke, don't fix it". Why is it important that Cup cars aren't rolling computers that have 87 different driver aids? It's a simply formula......V8, rear-drive, 4-speed stick, driver, Shut up and race....
They're 3400 pound sedans with old-tech pushrod V8s that make 850 hp and run as fast as 205 mph 3-wide, sometimes TOUCHING the car in front of, behind and/or next to them.
On every track except for the 'plate tracks, they are right on the ragged edge of a 4-wheel drift exiting every single turn for 500 miles.
On the plate tracks, there are usually positional swings of up to 15 spots in seconds....the top half of the field usually finishes the race within 2 seconds of eachother at 200 mph.
The engines turn well over 9000 RPM which is astronomical for a "stone-age" 358 small block.
Why everyone makes fun of NASCAR is beyond me....It's a classic case of "if it ai'nt broke, don't fix it". Why is it important that Cup cars aren't rolling computers that have 87 different driver aids? It's a simply formula......V8, rear-drive, 4-speed stick, driver, Shut up and race....
07-30-2009, 09:43 AM
#91
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Having a Corvette race in NASCAR would be simple enough - take any Chevy powered Cup Car and slap some decals on it and say Corvette on the front and you have a Corvette in NASCAR - or Say Cadillac for that matter.....
07-30-2009, 04:42 PM
#92
Safety Car
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They actually use "restrictors" to power down the vette in GT! class...
Corvette C6.R Engine: State-of-the-Art Small-Block V-8
The roots of the GM family tree of V-8 engines reach to the fabled small-block V-8 that was introduced in 1955. The current small-block V-8 shares virtually no components with the original design, yet it retains the longstanding virtues of compact size, simplicity, reliability and high specific output that have made the small-block V-8 the world's most successful production-based racing engine.
When the production LS1, the first of GM's new-generation small-block V-8s, debuted in the fifth-generation Corvette in 1997, it provided a foundation for the Corvette Racing engine program.
"Before the introduction of the LS1 small-block V-8, almost every V-8 engine used for racing dated back to designs that originated in the mid-'50s," said Mark Kent, director of GM Racing. "The GM small-block V-8 that has been the cornerstone of America's racing industry for more than 50 years is being replaced by derivatives of the LS series of engines. The LS engine family is truly the high-performance small-block V-8 of the future."
The race-prepared engines that power the Corvette C6.R race cars are more powerful than their showroom counterparts, but are still production small-block V-8s at heart. In fact, the heavy-duty blocks and cylinder heads designed by GM Racing engineers for Corvette Racing are based on the design of the production parts.
The ALMS rules mandate the use of air restrictors to equalize the performance potential of the wide variety of cars that compete in the series. The size of the restrictor is determined by the vehicle's weight, engine displacement, induction system (naturally aspirated or turbocharged) and other factors. The C6.R Corvette, for example, is required to breathe through two 31.8-mm restrictors. These orifices are about the size of a 50-cent coin.
Much like the carburetor restrictor plates used by NASCAR on superspeedways, the ALMS air restrictors limit airflow through the engine, thereby controlling the horsepower produced. Moreover, ALMS officials can change the size of the restrictor orifice to maintain a level playing field.
"The 7.0-liter engine combination allows us to run relatively low rpm to maximize fuel economy and reliability while producing extremely high torque numbers that make the cars very ‘driver-friendly' on a road course," explained GM Racing engineer John Rice.
The key components of the LS7.R racing engine are a heavy-duty, siamesed-bore cylinder block and CNC-ported competition cylinder heads. These components have close ties to their production counterparts.
"We designed the competition engine using as much of the production designs and processes as possible," said GM Racing engine specialist Roger Allen.
LS7 technology transfer
Examples of the synergy between the Corvette Z06's production LS7 small-block V-8 and the LS7.R racing engine that powers the Corvette C6.R race cars abound. Both are powered by 7-liter engines with dry-sump lubrication systems, CNC-ported cylinder heads, titanium valves and connecting rods, forged steel crankshafts and plate-honed cylinder bores. While the components and specifications of the street and competition engines are tailored to their specific environments, the thought process behind them is identical.
GM Powertrain, using valuable data gleaned from the factory Corvette Racing program, developed the 505-horsepower LS7 with many competition-derived components and design features. It takes production small-block performance to an unprecedented level while demonstrating the continuing adaptability of the engine's compact, cam-in-block design. It is, quite simply, the largest, most powerful production small-block V-8 GM has ever produced.
"In many ways, the LS7 production engine is a racing engine in a street car," said Dave Muscaro, assistant chief engineer of small-block V-8 engines for passenger cars."We've taken much of what we've learned over the years from the 7.0-liter Corvette Racing program and instilled it here. There really has been nothing else like it offered in a GM production vehicle."
Indeed, the LS7's engineers spent as much time at race tracks as they did at engine dynamometers. Everything from the cylinder heads to the unique dry-sump oiling system has a direct line back to the racing program. But while the LS7 has racing roots, it delivers its performance with uncompromising smoothness and tractability - qualities that make the Corvette Z06 a daily-driveable supercar.
The LS7's specifications are significant for a production engine:
505 horsepower @ 6300 rpm
470 lb.-ft. of torque @ 4800 rpm
7000-rpm redline
Unique engine block with larger 104.8-mm (4.125-inch) bores and pressed-in cylinder liners
Forged steel crankshaft with 101.6-mm (4-inch) stroke
Titanium connecting rods
Cast aluminum flat-top pistons
Racing-derived CNC-ported aluminum cylinder heads with titanium intake valves and sodium-filled exhaust valves
Dry-sump oiling system
11.0:1 compression ratio
Camshaft with 15-mm (.591-inch) lift
Hydroformed exhaust headers with unique "quad flow" collector flanges
"The racing experience enabled us to visualize how we could get more power out of the production engine," said Muscaro."How much you get depends on where the bar is set, and racing helped us set realistic goals. A street engine has the constraints of emissions, noise and durability standards, but the race engine really challenged us to produce maximum power from a given package.
"When we started to look at upgrading the LS6, the first thing we did was sit down with the race group and talk about what they had done to build a 7-liter small-block," Muscaro explained. "What did they do to the block to make the cylinder bores bigger, what did they do to the heads to increase the airflow? That was the key to creating the LS7."
The LS7's racing roots are evident in the cylinder block and reciprocating assembly, where an all-new aluminum block casting accommodates large, 104.8-mm-diameter (4.125-inch) cylinder bores. Aluminum flat-top pistons produce an 11.0:1 compression ratio. Lightweight titanium connecting rods link the pistons to a precision-balanced forged steel crankshaft with a 101.6-mm (4-inch) stroke. The titanium rods weigh just 480 grams apiece - almost 30 percent less than comparable steel rods.
Both the production LS7 and the C6.R race engines use dry-sump oiling systems designed to keep the engines properly lubricated during high-speed cornering. In the production Corvette Z06, an 8-quart reservoir delivers oil to the engine oil pump under the demanding conditions of cornering loads in excess of 1 g. While common in racing cars, the Corvette Z06 is one of just a handful of production vehicles - and the only production Corvette - to incorporate such a high-performance oiling system.
The LS7's CNC-ported aluminum cylinder heads are yet another legacy of the Corvette racing program. To ensure optimum airflow, the LS7 has straight, tunnel-like intake runners. Large by production-vehicle standards, the ports are designed to maintain high airflow velocity, providing excellent torque at low rpm and exhilarating horsepower at high rpm.
The cylinder heads feature 70-cc combustion chambers that are fed by huge, 56-mm-diameter titanium intake valves. The lightweight titanium valves each weigh 21 grams less than the stainless steel valves used in the standard Corvette LS2 small-block V-8, despite the valve head having 22-percent more area. They are complemented by 41-mm sodium-filled exhaust valves (vs. 39.4-mm valves in the LS2). To accommodate the large valve face diameters, the heads' valve seats are siamesed. Drawing on the experience of Corvette Racing, the LS7's valve angles are 12 degrees - versus 15 degrees for the LS2 - to enhance airflow.
Both the street and competition engines have evenly spaced, symmetrical intake and exhaust ports. Complete CNC porting of the LS7 and C6.R cylinder head is performed on state-of-the-art, five-axis milling machines, which carve out the intake ports, exhaust ports and combustion chambers with mathematical precision. Airflow through the LS7's cylinder head ports was improved 43 percent on the intake side and 26 percent on the exhaust side over the LS2.
"The LS series of GM small-block V-8 engines is going to have a long-term impact on the performance industry," said Kent. "It was Zora Arkus-Duntov's vision that Corvette should lead the way with race-ready parts and designs. I think he would be proud of what the GM small-block V-8 has achieved."
Copyright © 2009 Corvette Racing. All rights reserved.
Site hosted and maintained by the National Corvette Museum.
Corvette C6.R Engine: State-of-the-Art Small-Block V-8
The roots of the GM family tree of V-8 engines reach to the fabled small-block V-8 that was introduced in 1955. The current small-block V-8 shares virtually no components with the original design, yet it retains the longstanding virtues of compact size, simplicity, reliability and high specific output that have made the small-block V-8 the world's most successful production-based racing engine.
When the production LS1, the first of GM's new-generation small-block V-8s, debuted in the fifth-generation Corvette in 1997, it provided a foundation for the Corvette Racing engine program.
"Before the introduction of the LS1 small-block V-8, almost every V-8 engine used for racing dated back to designs that originated in the mid-'50s," said Mark Kent, director of GM Racing. "The GM small-block V-8 that has been the cornerstone of America's racing industry for more than 50 years is being replaced by derivatives of the LS series of engines. The LS engine family is truly the high-performance small-block V-8 of the future."
The race-prepared engines that power the Corvette C6.R race cars are more powerful than their showroom counterparts, but are still production small-block V-8s at heart. In fact, the heavy-duty blocks and cylinder heads designed by GM Racing engineers for Corvette Racing are based on the design of the production parts.
The ALMS rules mandate the use of air restrictors to equalize the performance potential of the wide variety of cars that compete in the series. The size of the restrictor is determined by the vehicle's weight, engine displacement, induction system (naturally aspirated or turbocharged) and other factors. The C6.R Corvette, for example, is required to breathe through two 31.8-mm restrictors. These orifices are about the size of a 50-cent coin.
Much like the carburetor restrictor plates used by NASCAR on superspeedways, the ALMS air restrictors limit airflow through the engine, thereby controlling the horsepower produced. Moreover, ALMS officials can change the size of the restrictor orifice to maintain a level playing field.
"The 7.0-liter engine combination allows us to run relatively low rpm to maximize fuel economy and reliability while producing extremely high torque numbers that make the cars very ‘driver-friendly' on a road course," explained GM Racing engineer John Rice.
The key components of the LS7.R racing engine are a heavy-duty, siamesed-bore cylinder block and CNC-ported competition cylinder heads. These components have close ties to their production counterparts.
"We designed the competition engine using as much of the production designs and processes as possible," said GM Racing engine specialist Roger Allen.
LS7 technology transfer
Examples of the synergy between the Corvette Z06's production LS7 small-block V-8 and the LS7.R racing engine that powers the Corvette C6.R race cars abound. Both are powered by 7-liter engines with dry-sump lubrication systems, CNC-ported cylinder heads, titanium valves and connecting rods, forged steel crankshafts and plate-honed cylinder bores. While the components and specifications of the street and competition engines are tailored to their specific environments, the thought process behind them is identical.
GM Powertrain, using valuable data gleaned from the factory Corvette Racing program, developed the 505-horsepower LS7 with many competition-derived components and design features. It takes production small-block performance to an unprecedented level while demonstrating the continuing adaptability of the engine's compact, cam-in-block design. It is, quite simply, the largest, most powerful production small-block V-8 GM has ever produced.
"In many ways, the LS7 production engine is a racing engine in a street car," said Dave Muscaro, assistant chief engineer of small-block V-8 engines for passenger cars."We've taken much of what we've learned over the years from the 7.0-liter Corvette Racing program and instilled it here. There really has been nothing else like it offered in a GM production vehicle."
Indeed, the LS7's engineers spent as much time at race tracks as they did at engine dynamometers. Everything from the cylinder heads to the unique dry-sump oiling system has a direct line back to the racing program. But while the LS7 has racing roots, it delivers its performance with uncompromising smoothness and tractability - qualities that make the Corvette Z06 a daily-driveable supercar.
The LS7's specifications are significant for a production engine:
505 horsepower @ 6300 rpm
470 lb.-ft. of torque @ 4800 rpm
7000-rpm redline
Unique engine block with larger 104.8-mm (4.125-inch) bores and pressed-in cylinder liners
Forged steel crankshaft with 101.6-mm (4-inch) stroke
Titanium connecting rods
Cast aluminum flat-top pistons
Racing-derived CNC-ported aluminum cylinder heads with titanium intake valves and sodium-filled exhaust valves
Dry-sump oiling system
11.0:1 compression ratio
Camshaft with 15-mm (.591-inch) lift
Hydroformed exhaust headers with unique "quad flow" collector flanges
"The racing experience enabled us to visualize how we could get more power out of the production engine," said Muscaro."How much you get depends on where the bar is set, and racing helped us set realistic goals. A street engine has the constraints of emissions, noise and durability standards, but the race engine really challenged us to produce maximum power from a given package.
"When we started to look at upgrading the LS6, the first thing we did was sit down with the race group and talk about what they had done to build a 7-liter small-block," Muscaro explained. "What did they do to the block to make the cylinder bores bigger, what did they do to the heads to increase the airflow? That was the key to creating the LS7."
The LS7's racing roots are evident in the cylinder block and reciprocating assembly, where an all-new aluminum block casting accommodates large, 104.8-mm-diameter (4.125-inch) cylinder bores. Aluminum flat-top pistons produce an 11.0:1 compression ratio. Lightweight titanium connecting rods link the pistons to a precision-balanced forged steel crankshaft with a 101.6-mm (4-inch) stroke. The titanium rods weigh just 480 grams apiece - almost 30 percent less than comparable steel rods.
Both the production LS7 and the C6.R race engines use dry-sump oiling systems designed to keep the engines properly lubricated during high-speed cornering. In the production Corvette Z06, an 8-quart reservoir delivers oil to the engine oil pump under the demanding conditions of cornering loads in excess of 1 g. While common in racing cars, the Corvette Z06 is one of just a handful of production vehicles - and the only production Corvette - to incorporate such a high-performance oiling system.
The LS7's CNC-ported aluminum cylinder heads are yet another legacy of the Corvette racing program. To ensure optimum airflow, the LS7 has straight, tunnel-like intake runners. Large by production-vehicle standards, the ports are designed to maintain high airflow velocity, providing excellent torque at low rpm and exhilarating horsepower at high rpm.
The cylinder heads feature 70-cc combustion chambers that are fed by huge, 56-mm-diameter titanium intake valves. The lightweight titanium valves each weigh 21 grams less than the stainless steel valves used in the standard Corvette LS2 small-block V-8, despite the valve head having 22-percent more area. They are complemented by 41-mm sodium-filled exhaust valves (vs. 39.4-mm valves in the LS2). To accommodate the large valve face diameters, the heads' valve seats are siamesed. Drawing on the experience of Corvette Racing, the LS7's valve angles are 12 degrees - versus 15 degrees for the LS2 - to enhance airflow.
Both the street and competition engines have evenly spaced, symmetrical intake and exhaust ports. Complete CNC porting of the LS7 and C6.R cylinder head is performed on state-of-the-art, five-axis milling machines, which carve out the intake ports, exhaust ports and combustion chambers with mathematical precision. Airflow through the LS7's cylinder head ports was improved 43 percent on the intake side and 26 percent on the exhaust side over the LS2.
"The LS series of GM small-block V-8 engines is going to have a long-term impact on the performance industry," said Kent. "It was Zora Arkus-Duntov's vision that Corvette should lead the way with race-ready parts and designs. I think he would be proud of what the GM small-block V-8 has achieved."
Copyright © 2009 Corvette Racing. All rights reserved.
Site hosted and maintained by the National Corvette Museum.
07-30-2009, 06:32 PM
#93
Drifting
Member Since: Jan 2007
Location: Melbourne FL
Posts: 1,878
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St. Jude Donor '09 & '11
Actually, Corvettes have run in NASCAR before and they didn't win. I read about it somewhere online earlier this week, but don't know where. But I'm sure you can find out the details with a little searching online.
