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JetFire
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I'm your huckleberry...
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MT test here:

 

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Hardcore Night Warrior
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Tons of reviews here, I haven't had a chance to check them all out yet.

Thanks for the link, but I dismissed any credence to the RT author when they kept referring to the LT2 as a, "small block". What did I say earlier, Ken? Anyways, in fairness I kept reading, they complained more than anything, which is stupid because they admit it's a pre-production car.

Common things I kept reading were how quiet and almost luxurious the car felt, which surprised me as these are the Z51 equipped cars. I would think the base ones would be quiet, while the Z51s would be louder. Disappointed to hear that they pipe in synthetic engine noises in the cabin if the RT article is true. I think Chevy realized they made it too cushy? lol.

2.8s 0-60 and near 11s flat 1/4s is incredible. Overall with regards to the other articles, it's hard to be definitive considering it's pre-production, but hopefully the 3LT package is cushiest while the 1 and 2LTs are more Corvette in sound/experience. I'm eager to hear what actual racing drivers comments are.
 

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From everything I've been reading, it sounds like the C8 doesn't handle quiet as well as the C7. Too much understeer. I bet Chevy did that on purpose for safety.

C/D also said that it isn't as fun to drive as the C7 or as engaging. I bet a big part of that is having no manual transmission.
 

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Super Moderator
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From everything I've been reading, it sounds like the C8 doesn't handle quiet as well as the C7. Too much understeer. I bet Chevy did that on purpose for safety.

C/D also said that it isn't as fun to drive as the C7 or as engaging. I bet a big part of that is having no manual transmission.
I'm not sure about the car not handling as well as the C7, but you are correct that the mid-corner push was designed in the vehicle dynamics software as a safety precaution for all those 'Vette owners that have never driven a mid-engine car. The MT comparo with the 911 speaks to this. As the article says, it's an issue when doing figure 8s but, in everyday driving, I do not see it as an issue. This was a very early production car that was virtually the equal, or superior, to the 911 in many areas and outright superior in terms of the quality of materials used and ride quality.


Ken.
 

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Also you have to consider that the C8 rides on Michelin Pilot Sport 4S ZP tires, which from what I hear are a big improvement over the C7 Michelin Pilot Super Sport tires.

Overall, it looks like GM got most of the Corvette right. Looking forward to more comparison and long term tests.
 

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C8 putting down some crazy dyno numbers?!


650 crank hp / 515whp after multiple runs from an NA V8? That is nuts. Maybe their dyno isn't calibrated or something?
 

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They keep on using 15% for driveterrain loss. Thats too high for a DCT with no driveshaft or torque converter. Should be around 10% or less.
 

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Hardcore Night Warrior
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They keep on using 15% for driveterrain loss. Thats too high for a DCT with no driveshaft or torque converter. Should be around 10% or less.
Even then, and if this is a production example, then it's comfortablly over 600 h.p. at the crank and close to 600 ft lbs.
My drag racing knowledge is limited, but I do know trap speed can give you a good indicator of HP. It's trapping 121 m.p.h., so does that trap accurately reflect the 600+ hp as seen here, or closer to the 490 ish as we are told its spec output is?
 

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iSPOOL
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My drag knowledge is limited too but at 120mph trap speed with the DCT and mid engine setup I could see it in 500hp+ range? Comparables would be cars like the GTR and 911s which have dual clutch transmissions and similar to numbers.
 

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Hardtopper
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Low 120's is 500WHP at best with a ~3600lb curb weight. I'm reserving judgement until we see Dynojet numbers (since they cannot be manipulated).
 

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They keep on using 15% for driveterrain loss. Thats too high for a DCT with no driveshaft or torque converter. Should be around 10% or less.
GM engineers alluded to the fact that DCT drivetrain losses are very low. I think your estimate of 10% or less could very well be true.

Low 120's is 500WHP at best with a ~3600lb curb weight. I'm reserving judgement until we see Dynojet numbers (since they cannot be manipulated).
I agree, Abram. I believe the 478 whp number is the number to be relied upon until more test results are provided, since a trap of 122 mph is what one would expect with 478 wheel.

To the magazine's credit, they went down a number of rabbit holes attempting to ascertain the reason (s) for the huge variances in dyno results. This was a very early production car (VIN #10) that had been flogged by the mainstream press for a couple weeks prior to the dyno test. While the results are likely an unexplained aberration, it will be interesting to see what a "cold" car does on a Dynojet. That said, the track says it all, and we would have to see traps approaching 130 mph in order to validate the highest number from the dyno test.


Ken.
 

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Chevy engineers also say that the drivetrain loss of a dual-clutch transmission, like the one in the Corvette, is less than 15 percent—but hesitated to give us an exact number (and even if it was zero loss, we still measured more wheel-horsepower than rated crank horsepower).
source:

Chevy says its less than 15%... still gonna use 15%... ok...
also mustang dyno... they could have just told the operator to make it read high so they can get their clickbait story
 

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That dyno definitely seems high for a 121-122mph 1/4 mile speed at 3600lbs. And I don't think they did anything really special to the LT1 to get those kind of gains.
 

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Hardcore Night Warrior
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^ LT2 is in the C8. Even though the car hasn't been out (limited info availability?), the info I can find is that the cam's exhaust lift has increased, the intake manifold has a re-design with shorter runners and different throttle body location/plenum design, and a dry-sump oiling system, which the engine has to be running to check. Some notables, 11.5 CR, this push-rod engine does have variable valve timing, and cylinder deactivation.
 

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^ LT2 is in the C8. Even though the car hasn't been out (limited info availability?), the info I can find is that the cam's exhaust lift has increased, the intake manifold has a re-design with shorter runners and different throttle body location/plenum design, and a dry-sump oiling system, which the engine has to be running to check. Some notables, 11.5 CR, this push-rod engine does have variable valve timing, and cylinder deactivation.
Yeah I know it's an LT2, I'm just saying that the LT2 is really an upgraded LT1 with just minor changes to give it a little more power. Same block, same crank, same rods, same crappy pistons..

And yes, Motor Trend's C8 dyno numbers were super inflated . You would think a major magazine would verify things before printing.
 
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