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Old 06-20-2013, 11:01 PM
  #21  
JoesC5
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Originally Posted by Guibo
Different wind tunnels could yield different results. A static one might be different from one with rollers in which the aerodynamic forces of wheel motion might come into play. Sport Auto put the C6 inside of DiamlerChrysler's wind tunnel, which they do for all of their supertests. That C6 recorded a Cd of 0.29, which is below 0.33 and close enough to the claim.
I agree, but when you put 6 different generations of the Corvette, back to back, in the same wind tunnel, with the same personnel running the test, then you can compare the delta between them. The C6 had higher coefficient of drag than the C5. GM claimed the opposite.
Old 06-21-2013, 12:17 AM
  #22  
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Originally Posted by Valleybacker
The GTR is easy to drive in the twisties due to the computer doing all the work.

To say it takes a "very far back seat", that's absurd.
I guess we need to define the back seat. As I said previously, the GTR will beat a corvette flat out on a short race as the AWD allows for more power to the ground. But that is it. With every other test and race comparison the corvette beat the GTR. And when it came to finish lines the corvette wasn't ahead by a few inches, it was more like a few car lengths.

So that is why I said very far back seat; the corvette wins the majority of comparisons. If your opinion of far back seat means, it can lap a GTR, then you are correct, that would be absurd. In fact, that wouldn't even be a comparison at that point. When comparing super cars, loosing by 3 seconds is a big deal. (I am not referring to any particular comparison, just making a point.)
Old 06-21-2013, 02:28 AM
  #23  
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Originally Posted by 60av8tor
Someone help me understand how a C7 Z51 that weighs more than a C6 Z51 goes as fast as a Z06 (that is lighter than both of 'em) 0-60, with 55 LESS horsepower than the aluminum framed Z06.

WTF, over ?
I've been trying my hardest to explain that the power to weight ratio is only one of many variables that contribute to how fast the car is. While there have been so many on here saying that the P:W ratio is all that matters and the reason the C6 Z06 will still dominate the C7, I've been trying to explain how gearing, stickier tires, stiffer chassis, majorly updated brakes, Gen 3 PTM, better downforce and aerodynamics, better gearing and eLSD are all major advantages the C7 Z51 has over the C6 Z06.

This goes on deaf ears a lot. If you keep listening to people who are in denial or people who ignore facts, you end up believing the same things.

On a personal note, I find it hilarious how many people said I don't know what I'm talking about. But I just happen to be good with numbers and estimating things like this. It's called observational logic.
Old 06-21-2013, 08:31 AM
  #24  
Dominic Toretto
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To the OP, there are SEVERAL variables that determine how fast a car will go. For starters, you can have two of the exact same car but change the gearing for one and make it a completely different animal. That's just one variable.

-Alex
Old 06-21-2013, 11:34 AM
  #25  
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Originally Posted by Dominic Toretto
To the OP, there are SEVERAL variables that determine how fast a car will go. For starters, you can have two of the exact same car but change the gearing for one and make it a completely different animal. That's just one variable.

-Alex
Stop it with that PHUNKY redneck physics.
Old 06-21-2013, 12:47 PM
  #26  
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LOL

-Alex
Old 06-21-2013, 02:02 PM
  #27  
vant
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I knew I should have checked that showboating Globetrotter algebra.

Old 06-21-2013, 02:12 PM
  #28  
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Originally Posted by SCM_Crash
I've been trying my hardest to explain that the power to weight ratio is only one of many variables that contribute to how fast the car is. While there have been so many on here saying that the P:W ratio is all that matters and the reason the C6 Z06 will still dominate the C7, I've been trying to explain how gearing, stickier tires, stiffer chassis, majorly updated brakes, Gen 3 PTM, better downforce and aerodynamics, better gearing and eLSD are all major advantages the C7 Z51 has over the C6 Z06.

This goes on deaf ears a lot. If you keep listening to people who are in denial or people who ignore facts, you end up believing the same things.

On a personal note, I find it hilarious how many people said I don't know what I'm talking about. But I just happen to be good with numbers and estimating things like this. It's called observational logic.
Logic and reason in C7 General? How dare you!!!....
Old 06-21-2013, 02:13 PM
  #29  
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Originally Posted by OnPoint
As fast as, might be a bit strong, but it's pretty close in performance, so I get your point.

Answer is torque, gearing and traction. And the VIR time speaks to the chassis and handling capabilities.


To me its a good thing the Base/Z51 C7 should be close or better than the out going Z06...So if the C7 is a Beast the C7Z06 will be a Super Beast...FWIW 13Z06 owner.
Old 06-21-2013, 02:32 PM
  #30  
vetteLT193
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There is also area under the curve when it comes to power. For a comparison, ask anyone that has driven a 96 LT4 vs a 95 LT1. They drive totally different because of the area under the curve.

The new 7 speed tranny in Z51 models has the C6 GS gearing in 1st through 6th which the Z06 did not have the advantage of.
Old 06-21-2013, 02:37 PM
  #31  
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Originally Posted by 60av8tor
Someone help me understand how a C7 Z51 that weighs more than a C6 Z51 goes as fast as a Z06 (that is lighter than both of 'em) 0-60, with 55 LESS horsepower than the aluminum framed Z06. WTF, over ?
Simple answer: it doesn't.

You can't compare Mero's C7 lap time with C&D's Z06 lap time. Different driver, day, and track configuration.
Old 06-21-2013, 02:52 PM
  #32  
herman2p
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Originally Posted by 60av8tor
Someone help me understand how a C7 Z51 that weighs more than a C6 Z51 goes as fast as a Z06 (that is lighter than both of 'em) 0-60, with 55 LESS horsepower than the aluminum framed Z06.

WTF, over ?
This may be a bit oversimplified, but hopefully it makes the right point.

From a stop these are the basic equation for acceleration

a(t)=Force(t)/mass = equation of motion for acceleration


Force(t) is the torque that the motor generates translated through the drivetrain and tires. Note: Mass is in the denominator, so higher mass lowers acceleration (BAD). You want the highest a(t) for the whole time you are accelerating, not just the millisecond the engine is peaking.

The key takeaway is that peak torque and horsepower numbers are not the complete story. It is the integrated torque/hp (summation of torque/hp over time) that the engine puts out that will determine how fast the car is.

In other words, you don't have the engine at peak torque/hp the whole time while you are accelerating from zero to 60. You have to look at what torque/hp the engine is putting out the whole time you are accelerating. So, it is possible that an engine with higher peak hp/torque numbers will be slower than an engine with a broader power curve but lower peak hp/torque numbers.

Does that make sense?? Even though it is possible, I am not sure I believe that the C7 is faster than a C6 Z06.

Last edited by herman2p; 06-21-2013 at 02:54 PM.
Old 06-21-2013, 10:51 PM
  #33  
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Originally Posted by DREAMERAK
Logic and reason in C7 General? How dare you!!!....
I know. I know. I'm a complete idiot for wasting my time. LOL
Old 06-22-2013, 12:50 AM
  #34  
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Originally Posted by SCM_Crash
I know. I know. I'm a complete idiot for wasting my time. LOL
I agree. You are wasting your time, becuase the numbers are out. You say you like numbers. I like numbers too. These would be official and per GM. To recap:

C7 Z51 0-60 3.8 1/4 mile 12.0 VIR lap 2:51:78
C6 GS. 0-60 3.95 1/4 mile 12.3
C6 Z06 0-60 3.7 1/4 mile 11.7
C6 ZR1 VIR lap 2:45:2

The ZO7 is known to lap a similar circuit 2sec slower than a ZR1, which puts it 5sec quicker than the C7 Z51. This is confirmed by GM from Milford data.

So why, in view of these official numbers, do you guys insist on perpetuating this fallacy that the C7 Z51 is as fast as a Z06 when the Z06 is quicker in every measure, and in some not even close?
Old 06-22-2013, 01:13 AM
  #35  
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I see you didn't post the c6 z06 vir time... The only one on the fast list is 2:58...
Old 06-22-2013, 01:29 AM
  #36  
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I am going to say something very forcefully and be rude to another forum member and that makes me right even though I don't have a clue what I am talking about.

Just thought I would join in.
Old 06-22-2013, 02:52 AM
  #37  
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Originally Posted by SCM_Crash
I see you didn't post the c6 z06 vir time... The only one on the fast list is 2:58...
If you look at the Bash video where Mero talks about the C7 time, you will see a list of times from the various C6 cars with various tires.

The Z06 was listed as 2:50 with GY Gen2 tires.

We also know that GM said the Z06 was 1 second faster on the C7 PSS tires than it was on its own tires. So that would make the Z06 time 2:49 with the same tires as the C7.

Therefore the C6 Z06 is about 2.8 seconds per lap faster than the C7 Z51 with equivalent tire compounds.

The GS on C7 tires would only about about 1.7 seconds slower than the C7, so the C7 is closer in lap time to the GS than it was to the Z06. Of course the video of the C7 looked very clean and smooth, which I think speaks more about the improvement in the car than the pure lap times.

-T

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Old 06-22-2013, 03:05 AM
  #38  
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Originally Posted by Trackaholic
If you look at the Bash video where Mero talks about the C7 time, you will see a list of times from the various C6 cars with various tires.

The Z06 was listed as 2:50 with GY Gen2 tires.

We also know that GM said the Z06 was 1 second faster on the C7 PSS tires than it was on its own tires. So that would make the Z06 time 2:49 with the same tires as the C7.

Therefore the C6 Z06 is about 2.8 seconds per lap faster than the C7 Z51 with equivalent tire compounds.

The GS on C7 tires would only about about 1.7 seconds slower than the C7, so the C7 is closer in lap time to the GS than it was to the Z06. Of course the video of the C7 looked very clean and smooth, which I think speaks more about the improvement in the car than the pure lap times.

-T
More like 2 seconds (not 2.8) until we know what the 10ths are for the C6 Z06 run on those tires.

Common denominators here... Lets not forget our basic math skills. 2.8 is closer to 3 seconds than 2.2 or 2.4.
Old 06-22-2013, 03:10 AM
  #39  
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Originally Posted by OnPoint
As fast as, might be a bit strong, but it's pretty close in performance, so I get your point.

Answer is torque, gearing and traction. And the VIR time speaks to the chassis and handling capabilities.
Probably has something to do with drivetrain efficiency, also.
Old 06-22-2013, 04:26 AM
  #40  
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Originally Posted by RocketGuy3
Probably has something to do with drivetrain efficiency, also.
I don't know that the drivetrain is that much more efficient. The smaller mass clutch probably helps, but I would venture a guess that we're only talking 1-1.5% recovered power. It's still heavy.

I think the only way we'll find out how efficient the drivetrain is will be when someone does a wheel dyno and an engine dyno back to back from the same car.


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