Beemer B773ER
Tire Trailblazer
Still not feeling it. 
Corvette (C8) [Official] Chevrolet Corvette Stingray (C8)
- Thread starter GCF
- Start date
The Chevrolet Corvette (C8) is the eighth generation of the Corvette sports car manufactured by American automobile manufacturer Chevrolet. It is the first rear mid-engine Corvette since the model's introduction in 1953, differing from the traditional front mid-engine design started in 1963. The C8 was announced in April 2019, and the coupe made its official debut on July 18, 2019, in Tustin, California.
DeDe
Subscriber
Yes: because it's an American car, the claimed 0-60mph time of 2.8 s is with 1-ft-rollout. It's an RWD car, so the one feet rolling-out needs at least 0.2 seconds. So the real 0-60mph time is 3.0 s. Add another 0.2 seconds for the gap between 60mph (97 kph) and 100 kph and tadaaaa, you have a European acceleration time of 3.2 sec 0-100 kph. Same as the time of a healthy 992 Carrera S with "only" 450 ps.
Still impressed? 
bmwz4coupe
Subscriber
Is GM relly refearing to a roll-out 0-60 time? Is it normal that american manufacteurs use roll-out when stating official 0-60 times?
DeDe
Subscriber
That's the easiest way to make a car "faster", yes.
tristatez28lt1
Tire Trailblazer
The lift system that can store 1000 locations is very cool. I always wondered why OEMs don't do that through GPS.
hoffmeister_fan
Kraftwagen König
Very Ferrari spec in the above vid.
Stopped by my local dealer a few weeks ago inquiring about it...2 intersting points the sales rep brought up 1) Chevy's going to tour the C8 around the country, so I'll get to see it in mid-Sept, and 2) lots of mid-30's folks like myself are inquiring about it, so with regards to the potential of drawing a younger crowd, at least this anecdotal bit is pointing to Chevy doing the right thing with the C8. The folks in the dealer were positively giddy about this. Can't wait to check one out in person.
Stopped by my local dealer a few weeks ago inquiring about it...2 intersting points the sales rep brought up 1) Chevy's going to tour the C8 around the country, so I'll get to see it in mid-Sept, and 2) lots of mid-30's folks like myself are inquiring about it, so with regards to the potential of drawing a younger crowd, at least this anecdotal bit is pointing to Chevy doing the right thing with the C8. The folks in the dealer were positively giddy about this. Can't wait to check one out in person.
They started, they have no peace
kingjr9000
Das Beste Enthusiast
From MT
You've heard the rumors and you've seen the leaked CAD drawings. The car world has been speculating about overhead cams and turbochargers and flat-plane cranks in the backs of C8 Corvettes for months now, but we've confirmed with a deep source on the Corvette team that the upcoming C8.R race car and, more crucially, the C8 Corvette Z06 will be powered by a flat-plane-crank twin-turbo dual-overhead-cam V-8.
"Everyone thinks it will be a small block, but it won't be," said our source. "Listen to the race car."
We did, and if you've ever seen the current C7.R car live, you know the roar of the pushrod LS7.R engine is unmistakable. Compare the above video, which shows a camouflaged C8.R testing at Sebring, to the one below. The C8.R exhibits an entirely different exhaust note, one consistent with a flat-plane-crank engine design. Key characteristics to listen for: a higher-pitched exhaust note, a consistent exhaust note without the pushrod's staccato bass line, higher RPM than a pushrod motor typically reaches characterized by longer times between upshifts, and lightning quick downshifts wherein the engine spins up to higher RPM much faster than a pushrod engine.
That last part helps explain why Chevrolet would do this. After all, Corvette Racing has won the 24 Hours of Le Mans eight times in 21 attempts with pushrod engines. As with the move to a mid-engine layout, the switch to a flat-plane crank is all about performance.
Consider the advantages. Flat-plane-crank engines have smaller, lighter crankshafts which can spin up faster than cross-plane-crank engines and lose less power to rotational inertia. The change in firing order also allows for better exhaust scavenging than a cross-plane crank. Exhaust scavenging, the method of pulling the last exhaust gases out of a cylinder faster using reflected pressure waves, improves performance and combustion efficiency—both crucial in racing.
Of course, flat-plane cranks have a big disadvantage in V-8 engines: balance. The whole reason Cadillac engineered the cross-plane crankshaft for V-8 engines back in the 1920s was to smooth out the engine. While cross-plane-crank V-8s are naturally balanced due to the order in which the pistons rise and fall in the block, flat-plane-crank V-8s have only half their vibrations cancelled out naturally, and the vibrations only get worse as engine speeds increase. Because the vibrations are caused by the movements of the pistons themselves, lightweight pistons and short strokes can help reduce (but not eliminate) the vibration of a flat-plane-crank engine. Aside from being annoying in the cockpit, vibrations can damage components or cause them to wear out more quickly.
Chevrolet, clearly, has calculated the performance advantage of lightening the rotating assembly and improving scavenging are worth the expense of designing a new engine, which explains the flat-plane crank. Why not a flat-plane crank pushrod engine, though? While it's mechanically possible, there's no advantage. Exhaust scavenging works better the faster an engine spins, and getting high RPM out of an engine requires a robust valvetrain. Even the best pushrod engine, the mighty LS7, maxxes out at 7,000 RPM. At higher engine speeds, flex in the valvetrain hurts precision and stability, which hurt performance. Ford's 5.2-liter Voodoo flat-plane crank V-8 doesn't spin to 8,250 RPM because of the crank, it's because of the advanced dual-overhead cam valvetrain.
That explains the flat-plane crankshaft and blasphemous dual-overhead cams, but just keeping up with Ford doesn't explain the turbos. Le Mans does. Le Mans' sanctioning body, the ACO, uses a formula called "Balance of Power" to attempt to level the playing field between different engine types and sizes, and for the past two years it's favored turbocharged engines from Ford and Ferrari to Corvette's detriment. Critically, Balance of Power can be adjusted simply by changing the maximum boost pressure of a turbocharged engine, whereas the naturally aspirated C7.R is forced to breathe through CNC-machined metal intake restrictors which have to be made from scratch.
Where would Chevrolet get such an engine? Why, from Cadillac, of course. Not quite, though. Even though Cadillac's new 4.2-liter twin-turbo DOHC Blackwing V-8 is built at the Corvette's engine plant in Bowling Green, Kentucky, GM has been adamant it's exclusive to Cadillac. How exclusive? Cadillac President Steve Carlisle told us Corvette would get it "over my dead body" and even Corvette champion and GM President Mark Reuss has said the engine hasn't even been test-fit in the C8 because it's a Cadillac engine.
Carlisle and Reuss may be splitting hairs, though. While the Z06 and C8.R's engine may not simply be a Blackwing with the wick turned up, it's likely to have a lot in common with Cadillac's engine but with enough different to make it a game of semantics. For starters, the Blackwing is a cross-plane-crank engine, so that would have to change. More critically, the Blackwing is a hot-vee design, a reverse-flow engine which puts its turbochargers in the valley between the heads rather than hanging off the sides of the engine. The leaked CAD drawings of a supposed twin-turbo DOHC C8 engine clearly show a traditional design with outboard turbos and the intake in the valley. At minimum, the Blackwing's crankshaft and heads would need to change, and that's a huge amount of work.
It doesn't necessarily mean starting over from scratch, though. The Blackwing was designed, in Cadillac's words, to be a "compact, mass-efficient" design which emphasized power-density and packaging, both important in the C8's small engine compartment. To share development costs, it's possible the C8 motor could use the Blackwing's block, and much of what was learned in developing the Blackwing's heads could be reused in the reconfigured Corvette heads.
There's one more change that would have to be made: bore. The Blackwing is an under-square engine—its stroke is longer than the diameter of its cylinder bores. Good for reliability and torque, bad for high-RPM performance. All modern flat-plane-crank V-8s, from Ford to Ferrari to McLaren, use over-square engines to reduce piston speed and quell those nasty flat-plane vibrations. Assuming Chevrolet doesn't change the stroke, the Blackwing would need to be bored out, increasing the displacement.
Don't expect a 5.5-liter displacement, though. Many outlets have tossed this number around without any basis. It may have come from the C7.R's engine, which is restricted by IMSA racing rules to 5.5 liters, and the old rule states "there's no replacement for displacement." Except there is. It's called forced induction, that's where the turbos come in. More important than that, though, larger displacement (bigger bores and longer strokes) means bigger vibrations, which is why it was so shocking to see Ford launch a 5.2-liter flat-plane-crank V-8. There's a reason Ferrari's flat-plane-crank twin-turbo DOHC V-8 is 3.9 liters and McLaren's is 3.8. Expect the C8's displacement to grow from the Blackwing's 4.2 liters, but fall well short of the 5.5-liter number that's been thrown around. The number of issues Ford has had with Voodoo engine failures alone should dispel any notion of Chevrolet going to an even larger displacement.
According to Chevrolet, the C8.R race car will be revealed sometime this fall. When it does, take a good look under the engine cover, because what you see there is what you'll be getting in the next Z06, and it won't have pushrods.
You've heard the rumors and you've seen the leaked CAD drawings. The car world has been speculating about overhead cams and turbochargers and flat-plane cranks in the backs of C8 Corvettes for months now, but we've confirmed with a deep source on the Corvette team that the upcoming C8.R race car and, more crucially, the C8 Corvette Z06 will be powered by a flat-plane-crank twin-turbo dual-overhead-cam V-8.
"Everyone thinks it will be a small block, but it won't be," said our source. "Listen to the race car."
We did, and if you've ever seen the current C7.R car live, you know the roar of the pushrod LS7.R engine is unmistakable. Compare the above video, which shows a camouflaged C8.R testing at Sebring, to the one below. The C8.R exhibits an entirely different exhaust note, one consistent with a flat-plane-crank engine design. Key characteristics to listen for: a higher-pitched exhaust note, a consistent exhaust note without the pushrod's staccato bass line, higher RPM than a pushrod motor typically reaches characterized by longer times between upshifts, and lightning quick downshifts wherein the engine spins up to higher RPM much faster than a pushrod engine.
That last part helps explain why Chevrolet would do this. After all, Corvette Racing has won the 24 Hours of Le Mans eight times in 21 attempts with pushrod engines. As with the move to a mid-engine layout, the switch to a flat-plane crank is all about performance.
Consider the advantages. Flat-plane-crank engines have smaller, lighter crankshafts which can spin up faster than cross-plane-crank engines and lose less power to rotational inertia. The change in firing order also allows for better exhaust scavenging than a cross-plane crank. Exhaust scavenging, the method of pulling the last exhaust gases out of a cylinder faster using reflected pressure waves, improves performance and combustion efficiency—both crucial in racing.
Of course, flat-plane cranks have a big disadvantage in V-8 engines: balance. The whole reason Cadillac engineered the cross-plane crankshaft for V-8 engines back in the 1920s was to smooth out the engine. While cross-plane-crank V-8s are naturally balanced due to the order in which the pistons rise and fall in the block, flat-plane-crank V-8s have only half their vibrations cancelled out naturally, and the vibrations only get worse as engine speeds increase. Because the vibrations are caused by the movements of the pistons themselves, lightweight pistons and short strokes can help reduce (but not eliminate) the vibration of a flat-plane-crank engine. Aside from being annoying in the cockpit, vibrations can damage components or cause them to wear out more quickly.
Chevrolet, clearly, has calculated the performance advantage of lightening the rotating assembly and improving scavenging are worth the expense of designing a new engine, which explains the flat-plane crank. Why not a flat-plane crank pushrod engine, though? While it's mechanically possible, there's no advantage. Exhaust scavenging works better the faster an engine spins, and getting high RPM out of an engine requires a robust valvetrain. Even the best pushrod engine, the mighty LS7, maxxes out at 7,000 RPM. At higher engine speeds, flex in the valvetrain hurts precision and stability, which hurt performance. Ford's 5.2-liter Voodoo flat-plane crank V-8 doesn't spin to 8,250 RPM because of the crank, it's because of the advanced dual-overhead cam valvetrain.
That explains the flat-plane crankshaft and blasphemous dual-overhead cams, but just keeping up with Ford doesn't explain the turbos. Le Mans does. Le Mans' sanctioning body, the ACO, uses a formula called "Balance of Power" to attempt to level the playing field between different engine types and sizes, and for the past two years it's favored turbocharged engines from Ford and Ferrari to Corvette's detriment. Critically, Balance of Power can be adjusted simply by changing the maximum boost pressure of a turbocharged engine, whereas the naturally aspirated C7.R is forced to breathe through CNC-machined metal intake restrictors which have to be made from scratch.
Where would Chevrolet get such an engine? Why, from Cadillac, of course. Not quite, though. Even though Cadillac's new 4.2-liter twin-turbo DOHC Blackwing V-8 is built at the Corvette's engine plant in Bowling Green, Kentucky, GM has been adamant it's exclusive to Cadillac. How exclusive? Cadillac President Steve Carlisle told us Corvette would get it "over my dead body" and even Corvette champion and GM President Mark Reuss has said the engine hasn't even been test-fit in the C8 because it's a Cadillac engine.
Carlisle and Reuss may be splitting hairs, though. While the Z06 and C8.R's engine may not simply be a Blackwing with the wick turned up, it's likely to have a lot in common with Cadillac's engine but with enough different to make it a game of semantics. For starters, the Blackwing is a cross-plane-crank engine, so that would have to change. More critically, the Blackwing is a hot-vee design, a reverse-flow engine which puts its turbochargers in the valley between the heads rather than hanging off the sides of the engine. The leaked CAD drawings of a supposed twin-turbo DOHC C8 engine clearly show a traditional design with outboard turbos and the intake in the valley. At minimum, the Blackwing's crankshaft and heads would need to change, and that's a huge amount of work.
It doesn't necessarily mean starting over from scratch, though. The Blackwing was designed, in Cadillac's words, to be a "compact, mass-efficient" design which emphasized power-density and packaging, both important in the C8's small engine compartment. To share development costs, it's possible the C8 motor could use the Blackwing's block, and much of what was learned in developing the Blackwing's heads could be reused in the reconfigured Corvette heads.
There's one more change that would have to be made: bore. The Blackwing is an under-square engine—its stroke is longer than the diameter of its cylinder bores. Good for reliability and torque, bad for high-RPM performance. All modern flat-plane-crank V-8s, from Ford to Ferrari to McLaren, use over-square engines to reduce piston speed and quell those nasty flat-plane vibrations. Assuming Chevrolet doesn't change the stroke, the Blackwing would need to be bored out, increasing the displacement.
Don't expect a 5.5-liter displacement, though. Many outlets have tossed this number around without any basis. It may have come from the C7.R's engine, which is restricted by IMSA racing rules to 5.5 liters, and the old rule states "there's no replacement for displacement." Except there is. It's called forced induction, that's where the turbos come in. More important than that, though, larger displacement (bigger bores and longer strokes) means bigger vibrations, which is why it was so shocking to see Ford launch a 5.2-liter flat-plane-crank V-8. There's a reason Ferrari's flat-plane-crank twin-turbo DOHC V-8 is 3.9 liters and McLaren's is 3.8. Expect the C8's displacement to grow from the Blackwing's 4.2 liters, but fall well short of the 5.5-liter number that's been thrown around. The number of issues Ford has had with Voodoo engine failures alone should dispel any notion of Chevrolet going to an even larger displacement.
According to Chevrolet, the C8.R race car will be revealed sometime this fall. When it does, take a good look under the engine cover, because what you see there is what you'll be getting in the next Z06, and it won't have pushrods.
bmwz4coupe
Subscriber
Now we are talking.....
Funny this is that it won't be a top dog. There will be a hybrid version also. Looks like its gonna be a hypercar Corvette.
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Chevrolet
Chevrolet is an American automobile division of the manufacturer General
Motors (GM). In North America, Chevrolet produces and sells a wide range
of vehicles, from subcompact automobiles to medium-duty commercial trucks.
Due to the prominence and name recognition of Chevrolet as one of General Motors'
global marques, "Chevrolet" or its affectionate nickname 'Chevy' or is used at
times as a synonym for General Motors or its products, one example being the GM
LS1 engine, commonly known by the name or a variant thereof of its progenitor,
the Chevrolet small-block engine.
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