Jawnathin

Anyone have any quantifiable data on how much of an improvement the Z07 package provides, given they have equal tires?

The problem I've had throughout my research is that the non-Z07 cars are typically on the crappy OEM Goodyears while nearly all of the latest Z07 results come from the Pilot Sport Cups. I know both cars are very fast, but given the difference in tire compound, the results would seem inappropriate to compare as the results are skewed heavily towards the car equipped with the grippier tire.

So does anyone have track result times or data for a Z06 vs Z07 on equal tires like the Pilot Sport PS2s? I would like to know how much benefit the MRC & Carbon Brakes provide on the track.

Thanks.

AzDave47

No hard data, but I'd guess about 1/2 second on a 1 min. 30 sec. lap. You could get possibly .2 sec back of that by getting Bilsteins/DRM Bilsteins/ Pfadt fo $300/$450/$600, but they wouldn't have the street/track flexibility of the MRC.

Also, the carbon brakes would be more reliable on the track, but then you have that big $$$$ when you have to replace them (pads and rotors).

Most of the time difference is the PSC tires, which you equalized out of the equation, rightly.

The driver could easily make 2-4 seconds difference, depending on skill level (range from good to pro, not novice.

Jawnathin

Thanks Dave. I appreciate the insight. After hearing how magical PCM and MCR is, it is not as big of a difference as I would have thought.

Though for clarity (I read the first and last sentence as possibly conflicting) you are suggesting that given equal drivers, the difference between a Z06 and Z07 car is about half a second on a 1:30 lap?

Then a good vs pro driver could account for 2-4 seconds on either platform? Meaning the cars are so close, that a very slightly better driver could easily make up the difference even if they were in the 'slower' car?

Would also welcome other impressions or thoughts as well.

AzDave47

No conflict, given equal drivers, Z07 option 1/2 sec. faster that Z06.

Re good driver vs pro, yes the pro would more than make up the Z07 difference. Good HPDE drivers do not realize how much the pro driver can do. Yhe big difference is not in slow corners (everyone is brave at 40 MPH) but in the high speed high risk corners followed by a good straight. That said, top amateur drivers can be fairly close to the pro driver.

More on point here, you (generically speaking as I don't know your skill level) could spend less than the difference between the Z06 and the Z07 option on top driver's ed (track) and be quicker in the Z06 than with current skills in the Z07 option.

Jawnathin

Got it, thanks Dave. I totally understand, those pros are on a whole other level.

My curiosity stems after reading about all these blistering lap times on Z06s with the Z07 package and wanted to see how much of an advantage those cars had over a regular Z. The specific test which generated this question are those from C&Ds Lightning Lap.

I couldn't understand why there was such a large delta between the Z07 and non-Z07 cars and how close the GS/Z51 were to the Z06. It doesn't make sense how poor those times are other than it was just a poor showing for the 06 & 07 cars.

2:53.5 2010 CHEVROLET CORVETTE Z06 (Z07, PS2)
2:58.2 2007 CHEVROLET CORVETTE Z06
2:58.5 2010 CHEVROLET CORVETTE GRAND SPORT
3:01.1 2006 CHEVROLET CORVETTE Z06
3:03.6 2008 CHEVROLET CORVETTE (Z51)



http://www.caranddriver.com/features...to-2012-page-8

3LZZ06

Keep in mind that the conditions aren't necessarily the same when these times were recorded, so that will also play into the time equation...

0Louis @ LG Motorsports

Equal tires, the differences would be minimal. IE the difference would come in the loss of weight from the brakes.

AzDave47

Jawnathin, The PSC tires on the grand course at VIR are probably good for 4-6 seconds over the Goodyear EMT's on the other Z06's.

Also, the C&D editors imply they are taking the cars to the limit. I mentioned earlier about high speed, high risk corners making a difference and VIR has several of those.

In 2008 C&D ran a prep'd Gen 3 Miata in the Nelson Ledges 24 hour race. They qualified fast, but I saw the car way off in the boondocks several times. After it hit the tire wall for the third time they retired it. The Gen 1 Miata I was co-driving won overall and covered 1990 miles green flag to checker.

Jawnathin

Yeah, I understand weather has a lot to do with it, but unless it was raining or very damp out for the Z06s back in 2006 and 2007, I don't see how a GS would have been faster or nearly as fast as the Z if driver skill was equal. And thats a big IF.

Awesome. Great feedback, thank you!

I understand the PSCs can probably shave 4-6 seconds on VIR, but the Z07 time I mentioned earlier was on the PS2s! This is a nearly 8 second advantage over the Z06 they tested in 2006.

Also agree that C&D editors are probably not the best drivers, but given I don't have any other times to use and this was at least the same publication helps provide a little bit of consistency in this bench racing exercise.

I think this might be chalked up to just poor driving. Maybe the drivers they had back in 2006-07 aren't nearly as talented as the drivers they use now.

Luweegy

Here is a little Tid Bit I found on Autoweek. As to the run the Viper made at the ring.
Does the addition of a modified fifth gear nullify the vehicle as stock now? Also adjustable aero kit. Doesn't sound like showroom stock to me?

Read more: http://www.autoweek.com/article/2011...#ixzz1kXRKASVy

95jersey

Here is one way to look at it. The ZR1 with carbon brakes, magnetic dampers, and PS2 tires did VIR in 2:51.8. The new ZR1 with the same carbon brakes, magnetic dampers, BUT with the the new CUP tires did 2:50.7

Since both ZR1's had the same brakes and suspension, and HP...the difference of 1.1 seconds truly represents what the new tires can do. It is hard to compare a Z06 with a Z07 because the Z07 has the carbon brakes and magentic dampers to name a few. But it is safe to assume that the tires are worth about 1 second (give or take).

So take away about 1 second between the Z06 and Z07 and you got the difference of what the Z07 brakes and suspension are contributing.

LEAVINU

..... no wonder GS sales are through the roof. Let's not forget the 06 Z's were the lightest, and most would claim had the more aggressive tunes out of the box. All while the GS is pushing near 3275-3300lbs easily yet STILL hung right there with a Z06.

Even if weather was a factor, the fact that the GS is @150lbs heavier and down @75rwhp should equate to the Z being "secs" ahead regardless.

Interesting....

0Louis @ LG Motorsports

The issue here is we dont know what the deal is- Same day? Back to back? Same track conditions? same driver? Its hard to really nail down.

I know for a fact the cups are worth more than 1.1 second on a 3 minute lap.

Louis

GMuffley

cruzin2

Also remember that the shock valving on th 06 made the rear a little scitish. Also the zr1 has ps2s on it when it first came out. So compareing the goodyears to cup tires is to compare almost two different cars. For those that have run "R" compound tires.... Its a big deal.

95jersey

The problem is even with same driver you will never get truly identical numbers. Say it is 60F in the morning and by 2pm it is 85F. That will effect lap times. As you know the variables are endless. I was also suprised to see that the ZR1 only did 1.1 seconds better on the new CUP tires. I would also have thought it would have been better. But as you say, different car, driver and conditions.

jmorgan07z06

I would think that the added downforce of the Z07 would be worth something. Personally, I think my LG equipped Z06 (stock engine but added G2's, sway bars and stoptechs) will take both of them on the track.

Rock36

Like others have said we just really compare different lap times from different years for all the reasons others have mentioned. If you look at the results from other cars on the lightning lap you will see a variation of times all over. Case in point:

The GT500 ran a 3:11 in the 2006 Lightning Lap, and then it ran a 3:05.9 in the 2007 Lightning Lap. Those two GT500s were EXACTLY the same, yet there was a 5 second lap difference (unless one was actually a ringer).

Other cars did run more consistent times over the years like the M3 coupe, but that only makes it more difficult to find patterns or really compare LL results from different years since the results are all over the place.

So it really doesn't concern me that a GS ran a faster time than a Z06 on laps that were run 4 years apart, and it is equally difficult determining how much faster the Z06/Z07 is over an older Z06.