Open Track - C5 Z06 vs. C6 Z51
10-06-2005, 04:15 PM
#1
Instructor
Thread Starter
Member Since: Jun 2005
Location: Rocklin CA
Posts: 158
Likes: 0
Received 0 Likes
on
0 Posts
Open Track - C5 Z06 vs. C6 Z51
I really like the new C6. However, I don't want a car that is slower around the track than a C5 Z06, especially when I'm paying more for it. My understanding is that the C6 is around 85% as fast around a track as a C5 Z06. Is that about right?
What would I need to improve to make its performance equal with a C5 Z06?
The HP seems to be about the same as does the weight. Is it just the suspension and perhaps brakes?
Any explanation would be greatly appreciated.
I must also state that I don't care about drag race times. Acceleration is only 1/3 of what makes a good track car. I need information directly related to road racing.
Thanks
What would I need to improve to make its performance equal with a C5 Z06?
The HP seems to be about the same as does the weight. Is it just the suspension and perhaps brakes?
Any explanation would be greatly appreciated.
I must also state that I don't care about drag race times. Acceleration is only 1/3 of what makes a good track car. I need information directly related to road racing.
Thanks
10-06-2005, 04:47 PM
#2
Team Owner
One word - tires. Loose the run flats and you should just about equal a C5 Z. Cost about $1200 for some good non run-flats. Absent that about another 15 HP should close the gap.
Good luck
Tom
Good luck
Tom
10-06-2005, 05:15 PM
#4
Drifting
Member Since: Dec 2000
Location: Tellico Plains, Tn "Wolf" Official Corvette Guard Dog
Posts: 1,959
Likes: 0
Received 0 Likes
on
0 Posts
Cruise-In II Veteran
Cruise-In III Veteran
Originally Posted by chucky7
Does the C5 Z06 have non runflats from the factory?
10-06-2005, 05:43 PM
#6
Safety Car
The difference isn't anywhere near 85%, you must have heard that on the Z06 forum... 
From what I've seen, it's probably closer to 2-3%, and I agree that it's mostly in the tires and slightly more aggressive suspension.
The C6 Z51 brakes are better than C5 Z06 brakes. Z06 brakes are standard C5 parts with different pads. Z51 has bigger rotors along with better pads.
If you're really concerned about track performance, why wouldn't you just run real race tires? In that senario, the C6 will match the old Z06 easily, and you can take the roof off on the ride home.
From what I've seen, it's probably closer to 2-3%, and I agree that it's mostly in the tires and slightly more aggressive suspension.The C6 Z51 brakes are better than C5 Z06 brakes. Z06 brakes are standard C5 parts with different pads. Z51 has bigger rotors along with better pads.
If you're really concerned about track performance, why wouldn't you just run real race tires? In that senario, the C6 will match the old Z06 easily, and you can take the roof off on the ride home.
10-06-2005, 06:33 PM
#7
Burning Brakes
Member Since: Oct 2003
Location: Farmersville Texas
Posts: 760
Likes: 0
Received 27 Likes
on
11 Posts
Originally Posted by Flareside
The difference isn't anywhere near 85%, you must have heard that on the Z06 forum... From what I've seen, it's probably closer to 2-3%,....
From what I've seen, it's probably closer to 2-3%,....
10-06-2005, 07:50 PM
#8
I believe the 85% deal actually came from David Hill. He said their goal for the Z51 C6 was to be 85% as good as the C5 Z06. Maybe they are over achievers! The C6 is a very good package and the average owner will never see 100% of the performance of it or the C5 Z06.
10-06-2005, 08:29 PM
#9
Safety Car
The quotes I've seen from DH said that if the Z06 is 4 seconds a lap faster than the standard C5, then the C6 Z51 would get back 3 of those seconds. So, a road course would yield a 1 second difference between the cars, and that's pretty far from 85%, that's for sure.
Here's the quote:
What about on a road course? Dave Hill has said, "If the Z06 was four-seconds-a-lap faster than a base C5 (on an unidentified race track), the new Z51 takes back three of those seconds"
Here's the quote:
What about on a road course? Dave Hill has said, "If the Z06 was four-seconds-a-lap faster than a base C5 (on an unidentified race track), the new Z51 takes back three of those seconds"
10-06-2005, 08:35 PM
#10
Burning Brakes
I think he meant about 75% of the difference between the C5 base Vette and the C5 Z06 ... so 3 seconds of 4 equals about 75%. I THINK that's what he meant.
10-07-2005, 08:37 AM
#11
Team Owner
Member Since: Sep 2003
Location: Raleigh / Rolesville NC
Posts: 43,084
Likes: 0
Received 24 Likes
on
24 Posts
One of the biggest difference between the C5 ZO6 and the C6 Z51 is the most over looked. That is the LS1 edit ( for LS1and LS6 ) vs the LS2 edit software.
LS1 is more developed and can change many fetures, like the torque managment ( which to my understanding) LS2 still has a challange with.
The C5 ZO6 has had more time for aftermarket development and testing. The C6 is not there YET, but will be very soon.
It is not uncommon for C5 ZO6s with great tuner to get 375-385 RWHP out of the stock engine, stock air box and headers. the T1 race cars cars are tuned to these levels.
An other area is the suppnesion. The C5 ZO6 suppension is still a bit stiffer then the C6 Z51, and the C5s have the GM T1 road racing suppension avaible. the T1 for the C6 is not quite out yet. Gene from Fred Beans ( forum Vender) has a line on the C6 T1 spings and bars, but not the T1 shocks and A-arms with the poly bushings.
In short it is the development time the C5 has over the C6, but not for long.
and 3 to 4 sec a lap on any track is 300-400 feet / per lap. or even 1 sec per lap difference is still about 100-120 feet on a road course per lap. SO a 10 lap race on a 2 min per lap track is . . . . . ( give all other things are accounted for) 10 seconds slower or 1000-1200 feet behind about 1/4 to 3/8s a lap behind.
Again this is all speculation and bench talk on published NUMBERS. Driver skill has more to do with lap times then anything else.
Heck I have seen guys with 30+ years racing experience in stock Audi station wagons beat Vipers and ZO6s with drivers having little to no experience.
Seat time
seat time and more seat time will be mods every time.
LS1 is more developed and can change many fetures, like the torque managment ( which to my understanding) LS2 still has a challange with.
The C5 ZO6 has had more time for aftermarket development and testing. The C6 is not there YET, but will be very soon.
It is not uncommon for C5 ZO6s with great tuner to get 375-385 RWHP out of the stock engine, stock air box and headers. the T1 race cars cars are tuned to these levels.
An other area is the suppnesion. The C5 ZO6 suppension is still a bit stiffer then the C6 Z51, and the C5s have the GM T1 road racing suppension avaible. the T1 for the C6 is not quite out yet. Gene from Fred Beans ( forum Vender) has a line on the C6 T1 spings and bars, but not the T1 shocks and A-arms with the poly bushings.
In short it is the development time the C5 has over the C6, but not for long.
and 3 to 4 sec a lap on any track is 300-400 feet / per lap. or even 1 sec per lap difference is still about 100-120 feet on a road course per lap. SO a 10 lap race on a 2 min per lap track is . . . . . ( give all other things are accounted for) 10 seconds slower or 1000-1200 feet behind about 1/4 to 3/8s a lap behind.
Again this is all speculation and bench talk on published NUMBERS. Driver skill has more to do with lap times then anything else.
Heck I have seen guys with 30+ years racing experience in stock Audi station wagons beat Vipers and ZO6s with drivers having little to no experience.
Seat time
seat time and more seat time will be mods every time.
10-08-2005, 03:30 AM
#12
Race Director
I have both cars. The difference is more like 5% and it's not in acceleration: on a cool day, the C6 is just as fast, despite having a 3% final gearing disadvantage due to the bigger rear wheels. The primary difference is tires, so braking and cornering are not quite as good. Shock damping and compliance, on the other hand, are noticeably better. I think better shocks (my Z is an '02) and more suspension travel on the C6 are the contributors.The caveat here is that I am comparing stock GY F1 SC runflats on the C6 to the Nitto R2s I have on the Z - tires which are incredible and far better than the stock F1 SC.
I swapped the Z06 wheels onto the C6 and took it out for a drive. I did not go too far because the rear tires stuck out beyond the fender and I was afraid they would damage the fender under compression. But after a few corners, it was clear the C6 felt just like the Z. So the only difference to me is tires.
Now for the caveat: for some reason (perhaps agressive engine management due to high compression ratio), the LS-2 in the C6 just falls apart on a hot day. 68-75F, the thing is a monster - I like it better than the LS-6. But give it 95F and turn on the AC, and it becomes a DOG.
The good news is I have never encountered TM on my car, even when temps are cool and I rip the 1-2 shift hard. Maybe engine management is this is what people have confused with TM.
If ever a car needed cold air intake and a tune, it's this one.
I swapped the Z06 wheels onto the C6 and took it out for a drive. I did not go too far because the rear tires stuck out beyond the fender and I was afraid they would damage the fender under compression. But after a few corners, it was clear the C6 felt just like the Z. So the only difference to me is tires.
Now for the caveat: for some reason (perhaps agressive engine management due to high compression ratio), the LS-2 in the C6 just falls apart on a hot day. 68-75F, the thing is a monster - I like it better than the LS-6. But give it 95F and turn on the AC, and it becomes a DOG.
The good news is I have never encountered TM on my car, even when temps are cool and I rip the 1-2 shift hard. Maybe engine management is this is what people have confused with TM.
If ever a car needed cold air intake and a tune, it's this one.
10-08-2005, 03:41 AM
#13
Race Director
Oh, your question was about a track...I'm gonna get flamed for this, but I think that with both cars on race tires, (and assuming a cool day), the C6 will get the faster lap time, by a hair. The reasons are more engine torque and better weight distribution in the C6.
Before the Z, I had a 2000 coupe with bilsteins and hotchkis bars. Despite the 50 hp deficit, I actually turned similar lap times at Bragg Smith with the Coupe as I did with the Z06s. The rear end on the Z just never felt as planted to me, especially under heavy braking. At my other HPDEs, I had little trouble keeping up with the stock Z's on Hoosiers. None of the Vettes had trouble passing Vipers
I never got my own Z06 to a track, so I could not directly compare.
Before the Z, I had a 2000 coupe with bilsteins and hotchkis bars. Despite the 50 hp deficit, I actually turned similar lap times at Bragg Smith with the Coupe as I did with the Z06s. The rear end on the Z just never felt as planted to me, especially under heavy braking. At my other HPDEs, I had little trouble keeping up with the stock Z's on Hoosiers. None of the Vettes had trouble passing Vipers
I never got my own Z06 to a track, so I could not directly compare.
10-08-2005, 05:48 AM
#14
Instructor
Member Since: Sep 2003
Location: Baton Rouge LA
Posts: 200
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by TTRotary
I have both cars. The difference is more like 5% and it's not in acceleration: on a cool day, the C6 is just as fast, despite having a 3% final gearing disadvantage due to the bigger rear wheels. The primary difference is tires, so braking and cornering are not quite as good. Shock damping and compliance, on the other hand, are noticeably better. I think better shocks (my Z is an '02) and more suspension travel on the C6 are the contributors.The caveat here is that I am comparing stock GY F1 SC runflats on the C6 to the Nitto R2s I have on the Z - tires which are incredible and far better than the stock F1 SC.
I swapped the Z06 wheels onto the C6 and took it out for a drive. I did not go too far because the rear tires stuck out beyond the fender and I was afraid they would damage the fender under compression. But after a few corners, it was clear the C6 felt just like the Z. So the only difference to me is tires.
Now for the caveat: for some reason (perhaps agressive engine management due to high compression ratio), the LS-2 in the C6 just falls apart on a hot day. 68-75F, the thing is a monster - I like it better than the LS-6. But give it 95F and turn on the AC, and it becomes a DOG.
The good news is I have never encountered TM on my car, even when temps are cool and I rip the 1-2 shift hard. Maybe engine management is this is what people have confused with TM.
If ever a car needed cold air intake and a tune, it's this one.
I swapped the Z06 wheels onto the C6 and took it out for a drive. I did not go too far because the rear tires stuck out beyond the fender and I was afraid they would damage the fender under compression. But after a few corners, it was clear the C6 felt just like the Z. So the only difference to me is tires.
Now for the caveat: for some reason (perhaps agressive engine management due to high compression ratio), the LS-2 in the C6 just falls apart on a hot day. 68-75F, the thing is a monster - I like it better than the LS-6. But give it 95F and turn on the AC, and it becomes a DOG.
The good news is I have never encountered TM on my car, even when temps are cool and I rip the 1-2 shift hard. Maybe engine management is this is what people have confused with TM.
If ever a car needed cold air intake and a tune, it's this one.
I have both and agree with your comments though my ZO6 is far from stock now. However I live in Baton Rouge and have not noticed any power loss with the C6 due to the heat. My C6 has no mods other than pedals and Borla stingers.
10-08-2005, 07:49 AM
#15
Team Owner
Member Since: Sep 2003
Location: Raleigh / Rolesville NC
Posts: 43,084
Likes: 0
Received 24 Likes
on
24 Posts
The above comments from connor and TTRotary help show that the development time of the C5 and the LS1 software tuning played a big part.
The LS2 software for editing and tuning has had a year of aftermarket development and imporvments. Plus the eliminating the TPS issues to use better tires. Most of these minor issues are just about over come as there are many C6 Z51s now being built for T1 racing.
Like almost all cars, only a little devleopment time and look out . . .
The LS2 software for editing and tuning has had a year of aftermarket development and imporvments. Plus the eliminating the TPS issues to use better tires. Most of these minor issues are just about over come as there are many C6 Z51s now being built for T1 racing.
Like almost all cars, only a little devleopment time and look out . . .
10-08-2005, 11:11 AM
#16
Originally Posted by TTRotary
Oh, your question was about a track...I'm gonna get flamed for this, but I think that with both cars on race tires, (and assuming a cool day), the C6 will get the faster lap time, by a hair. The reasons are more engine torque and better weight distribution in the C6.
Before the Z, I had a 2000 coupe with bilsteins and hotchkis bars. Despite the 50 hp deficit, I actually turned similar lap times at Bragg Smith with the Coupe as I did with the Z06s. The rear end on the Z just never felt as planted to me, especially under heavy braking. At my other HPDEs, I had little trouble keeping up with the stock Z's on Hoosiers. None of the Vettes had trouble passing Vipers
I never got my own Z06 to a track, so I could not directly compare.
Before the Z, I had a 2000 coupe with bilsteins and hotchkis bars. Despite the 50 hp deficit, I actually turned similar lap times at Bragg Smith with the Coupe as I did with the Z06s. The rear end on the Z just never felt as planted to me, especially under heavy braking. At my other HPDEs, I had little trouble keeping up with the stock Z's on Hoosiers. None of the Vettes had trouble passing Vipers
I never got my own Z06 to a track, so I could not directly compare.
TT, I followed another of your posts on the Z06 forum comparing your 2002 Z06 to your C6.
You bring up several good points about the tire and wheel size differences between the C5 Z06 and the C6.
The Z06 uses a slightly wider tire, it uses a non runflat tire, and an 18 inch tire vs the 19 inch C6 rears.
However, I love to crunch numbers........ can you please tell me how you calculate the 3% gearing advantage that the C5 Z06 has over the C6 by virtue of the tire size?
I assume that you are referring to gears 1, 2, 3 and 4 because I believe that 5 and 6 are different on the Z06?
Thanks in advance.
And oh, yeah. You are indeed, very likely to get flamed by some for your above statement.
However since both you and Connor are owners of both cars, I, for one, and I am sure that many others here, most certainly respect your opinions.
10-08-2005, 05:02 PM
#17
Race Director
Originally Posted by EB20003
However, I love to crunch numbers........ can you please tell me how you calculate the 3% gearing advantage that the C5 Z06 has over the C6 by virtue of the tire size? I assume that you are referring to gears 1, 2, 3 and 4 because I believe that 5 and 6 are different on the Z06?
C6: 285mm x.7 (aspect x 2) / 25.4 (to get inches) + 19 = 26.854
Z06: 295mm x.7 (aspect x 2) / 25.4 (to get inches) + 18 = 26.129
C6 result / Z06 result: 1.028. On a dyno, that should be worth about 9.5HP and torque on a car putting down low 340s, as most C6s so far seem to be doing.
Numbers aside, the car felt a mite quicker on the Z06 wheels, but of course, that's totally subjective.
