Auto X-ing. What a difference between suspensions!
Thread Starter
Le Mans Master
Joined: Apr 2006
Posts: 5,933
Likes: 13
From: The Beautiful Inland Empire WA.
Auto X-ing. What a difference between suspensions!
Went to a Corvette's only autocross this morning and watching the cars go through the course, it was pretty obvious who had what:
1. Base suspension C6's -- ...the most body roll and tire squeel, seemed to be mostly from the front tires...through the slalom section, the back ends seemed to swing back and forth more too -- likely the body roll affecting vehicle dynamics.
2. Z51 C6's......noticeably faster through the slalom with much less body roll. A LOT less push from the front tires, and the rears seemed to stay planted and effective at much higher speeds.
3. There were no C6 ZO6's there but the C5 ZO6's were much faster, with NO body roll anywhere on the course. They were able to stab the throttle in places on the course that none of the other cars could do. Even sliding a little sideways coming out of the long sweeper into the slalom, they looked so much more in control.......
I did not try it today for a lot of reasons (I have the base suspension and it is not, I think, particularly well suited to this) but I AM going to get the Z51 sway bars and poly bushings just because I saw visual proof today of what the car is going to handle like with those!!!
1. Base suspension C6's -- ...the most body roll and tire squeel, seemed to be mostly from the front tires...through the slalom section, the back ends seemed to swing back and forth more too -- likely the body roll affecting vehicle dynamics.
2. Z51 C6's......noticeably faster through the slalom with much less body roll. A LOT less push from the front tires, and the rears seemed to stay planted and effective at much higher speeds.
3. There were no C6 ZO6's there but the C5 ZO6's were much faster, with NO body roll anywhere on the course. They were able to stab the throttle in places on the course that none of the other cars could do. Even sliding a little sideways coming out of the long sweeper into the slalom, they looked so much more in control.......
I did not try it today for a lot of reasons (I have the base suspension and it is not, I think, particularly well suited to this) but I AM going to get the Z51 sway bars and poly bushings just because I saw visual proof today of what the car is going to handle like with those!!!
Team Owner
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From: FL
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Suspensions are a HUGE deal in autocrossing. Hell, I'm getting ready to replace the shocks on my C6 Z just to be competitive.
Pro
Joined: Jun 2007
Posts: 598
Likes: 3
From: Farmington MI
Most of what you saw was likely driving. A great driver in a base car will look smooth and a hack will look awful in a new Z06.
People buy the Z51 and/or Z06 for a reason - they're going to AutoX and/or track the car. Save your time and money. Get out and drive and drive and drive. If you've never done it, the car as-is is way beyond your ability to explore its limits.
A C6 Z51 should have times similar to a C5 Z06 with the same driver.
Poly bushings will take you out of the stock class, and they're far from the weak link (and they're harsh and noisy - you'll hate them). A sway bar won't address much on is own either. A great driver in a neon will smoke a novice in a Z06 all day long.
IMHO...
Just get out there - it's a blast!
People buy the Z51 and/or Z06 for a reason - they're going to AutoX and/or track the car. Save your time and money. Get out and drive and drive and drive. If you've never done it, the car as-is is way beyond your ability to explore its limits.
A C6 Z51 should have times similar to a C5 Z06 with the same driver.
Poly bushings will take you out of the stock class, and they're far from the weak link (and they're harsh and noisy - you'll hate them). A sway bar won't address much on is own either. A great driver in a neon will smoke a novice in a Z06 all day long.
IMHO...
Just get out there - it's a blast!
Last edited by avizandum; Jul 27, 2008 at 08:57 PM.
Le Mans Master
Joined: Jun 2007
Posts: 7,610
Likes: 12
Add adjustable coilovers (loose the OEM shocks and leaf springs) and you will have a highly competitive suspension.
Instructor
Joined: Apr 2008
Posts: 172
Likes: 1
From: Roseville California
Poly bushings?? I have a buddy that added z-51 sways to 05-C6 now has clunk noise in rear sometimes when making slow right turn. Is this what you mean about "Harsh and Noisy".
Most of what you saw was likely driving. A great driver in a base car will look smooth and a hack will look awful in a new Z06.
People buy the Z51 and/or Z06 for a reason - they're going to AutoX and/or track the car. Save your time and money. Get out and drive and drive and drive. If you've never done it, the car as-is is way beyond your ability to explore its limits.
A C6 Z51 should have times similar to a C5 Z06 with the same driver.
Poly bushings will take you out of the stock class, and they're far from the weak link (and they're harsh and noisy - you'll hate them). A sway bar won't address much on is own either. A great driver in a neon will smoke a novice in a Z06 all day long.
IMHO...
Just get out there - it's a blast!
People buy the Z51 and/or Z06 for a reason - they're going to AutoX and/or track the car. Save your time and money. Get out and drive and drive and drive. If you've never done it, the car as-is is way beyond your ability to explore its limits.
A C6 Z51 should have times similar to a C5 Z06 with the same driver.
Poly bushings will take you out of the stock class, and they're far from the weak link (and they're harsh and noisy - you'll hate them). A sway bar won't address much on is own either. A great driver in a neon will smoke a novice in a Z06 all day long.
IMHO...
Just get out there - it's a blast!
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Pro
Joined: Jun 2007
Posts: 598
Likes: 3
From: Farmington MI
No. Depending where you put poly bushings, they offer little / no dampening and transmit all road noise (and feel - there is an upside). You will hear and feel every joint in the highway, bump in the road, etc. They do elimate deflection caused by soft, rubber bushings... A slow speed clunk is not likely from a sway bar - unless there's something strange going on and it's binding and it gets relief on a right-hand turn, but that seems unlikely...
Pro
Joined: Jun 2007
Posts: 598
Likes: 3
From: Farmington MI
Drifting
Joined: Nov 2005
Posts: 1,745
Likes: 35
From: Turlock CA
I did not try it today for a lot of reasons (I have the base suspension and it is not, I think, particularly well suited to this) but I AM going to get the Z51 sway bars and poly bushings just because I saw visual proof today of what the car is going to handle like with those!!!
I bought my base model (vs. Z51) knowing I would change many parts over time. But starting out, I added the Z06 shocks and bars as a quick cheap fix. For you, I recommend putting on the Z51/Z06 F bar and leaving the R base bar on. I found the best grip and times with this combo. Many autox-ers run no R bar. Get in lots of seat time before you worry about your shocks.
Keep in mind that the Z51's tires are grippier which accounts for much of their improved performance at the cost of tire wear. For now, run your stock tires and see if you enjoy autox. If you do, you'll find it cheaper to have a second set of wheels and tires to save your more expensive run-flats.
One more thing. You don't need more power to compete. Even against C5-6Z06s. So, save your money there.
--Dan
Pro
Joined: Jun 2007
Posts: 598
Likes: 3
From: Farmington MI
Many things can make a difference but seat time will help you the most.
I bought my base model (vs. Z51) knowing I would change many parts over time. But starting out, I added the Z06 shocks and bars as a quick cheap fix. For you, I recommend putting on the Z51/Z06 F bar and leaving the R base bar on. I found the best grip and times with this combo. Many autox-ers run no R bar. Get in lots of seat time before you worry about your shocks.
Keep in mind that the Z51's tires are grippier which accounts for much of their improved performance at the cost of tire wear. For now, run your stock tires and see if you enjoy autox. If you do, you'll find it cheaper to have a second set of wheels and tires to save your more expensive run-flats.
One more thing. You don't need more power to compete. Even against C5-6Z06s. So, save your money there.
--Dan
I bought my base model (vs. Z51) knowing I would change many parts over time. But starting out, I added the Z06 shocks and bars as a quick cheap fix. For you, I recommend putting on the Z51/Z06 F bar and leaving the R base bar on. I found the best grip and times with this combo. Many autox-ers run no R bar. Get in lots of seat time before you worry about your shocks.
Keep in mind that the Z51's tires are grippier which accounts for much of their improved performance at the cost of tire wear. For now, run your stock tires and see if you enjoy autox. If you do, you'll find it cheaper to have a second set of wheels and tires to save your more expensive run-flats.
One more thing. You don't need more power to compete. Even against C5-6Z06s. So, save your money there.
--Dan
Forgot to mention the rubber...
1st mod - a good alignment - I run -1.2 camber, 8.0 caster, 0 toe (front), -0.7 camber, 1/16 toe in (rear) on a DD with no problems
2nd mod - good tires
3rd mod - starts getting subjective
Thread Starter
Le Mans Master
Joined: Apr 2006
Posts: 5,933
Likes: 13
From: The Beautiful Inland Empire WA.
While I agree with those who have said that driver experience and talent is the largest part of going quickly during autocrossing......I still say that everything else being equal as far as the driver, making improvements to how the same car handles on the same course should improve your time.......in other words --- putting the same talented driver in a ZO6 should make them much faster on the same course than that driver in any base suspension Corvette......no one can overcome inferior vehicle dynamics with only driving talent!!! That's like saying your street C6 could go out and keep up with a C6R --- ain't gonna' happen.
Last edited by C6NRED; Jul 28, 2008 at 12:05 PM.
Drifting
Joined: Nov 2005
Posts: 1,745
Likes: 35
From: Turlock CA
While I agree with those who have said that driver experience and talent is the largest part of going quickly during autocrossing......I still say that everything else being equal as far as the driver, making improvements to how the same car handles on the same course should improve your time.......in other words --- putting the same talented driver in a ZO6 should make them much faster on the same course than that driver in any base suspension Corvette......no one can overcome inferior vehicle dynamics with only driving talent!!! That's like saying your street C6 could go out and keep up with a C6R --- ain't gonna' happen.
Something that I have found helpful over the 40+ years I've been doing this is to have one of the "hot shoes" drive your car occasionally. It will let you know how "equal" you are as a driver. From there, you can decide on what needs improvement.
--Dan