First time auto-crossing C6Z with original Eagle F1s...
10-20-2018, 04:07 PM
#1
First time auto-crossing C6Z with original Eagle F1s...
Recently picked up a 13 C6Z and took it for an autocross today with SCCA. Ambient temperature 60 degrees and initially course was wet due to rain last night. Car is 100% stock and has original F1 eagle tires.
The car behaved wildly to say the least. Literally couldn't even go 50% throttle in 2nd exiting a corner without over-steering and/or spinning. The car has a lot of potential to drive fast, but was off pace by 9-10 seconds from other C6Zs with proper tires/setup.
I am figuring it was the tires that made the car have basically no grip throughout the course. A fellow auto-crosser said the stock alignment is also a big issue and the handling should improve greatly with a proper alignment even with stock tires.
So right now I am trying to figure out a 18 inch front/rear rim setup for BFG rival tires (275 & 335 width) that would accommodate a possible BBK upgrade in future when I start tracking the car like AP racing or Stoptech. Any suggestions?
FYI I plan on auto-crossing the car again with stock setup till end of season and maybe next year look into rims/tires first thing and alignment to balance out the car and improve grip on throttle. I really want to rev this motor out and feel the full power on course.
The car behaved wildly to say the least. Literally couldn't even go 50% throttle in 2nd exiting a corner without over-steering and/or spinning. The car has a lot of potential to drive fast, but was off pace by 9-10 seconds from other C6Zs with proper tires/setup.
I am figuring it was the tires that made the car have basically no grip throughout the course. A fellow auto-crosser said the stock alignment is also a big issue and the handling should improve greatly with a proper alignment even with stock tires.
So right now I am trying to figure out a 18 inch front/rear rim setup for BFG rival tires (275 & 335 width) that would accommodate a possible BBK upgrade in future when I start tracking the car like AP racing or Stoptech. Any suggestions?
FYI I plan on auto-crossing the car again with stock setup till end of season and maybe next year look into rims/tires first thing and alignment to balance out the car and improve grip on throttle. I really want to rev this motor out and feel the full power on course.
10-21-2018, 04:34 AM
#2
Race Director
i believe have a useful lifespan.. if i remember corr4ctly its about 4 years. take a look on tire radks website i think they reference that. they’ve probably date coded out.
10-21-2018, 08:49 AM
#3
Goodyear Eagles F1 in C6 days had a 2 year useful life, after that they started to harden so they would look like they still had tread life but the hard tire had no grip and got noisier. When fresh they did have good grip if they got hot like on a road course. I don’t know if they would get hot enough quickly enough for autocross but if they are original tires on a 2013 car I wouldn’t use them at all, dry grip is greatly reduced, wet grip is gone and they will be extremely noisy. When I had a C5 I gave away the tires and put on Michelins and the sound, handling drastically improved in ordinary driving. YMMV
10-23-2018, 05:03 PM
#4
Burning Brakes
Most autocross courses have very short if any straights, they usually will instead be turned into a slalom. I rarely get to WOT on an autocross and usually get into second gear as soon as possible and leave it there. (I also have a C6Z and previously autocrossed a C5Z) Shifting slows you down and there is so much torque in first gear I would wind up spinning the tires even with 50% throttle. Autocross is technical and not about brute force so wanting to feel the power on a course is not really the best place as it is more about feeling the G’s as you slalom or turn. I would recommend a HPDE or beginner track day with an instructor if you want to feel the brute force of our LS7 but first get rid of those tires and go with stock tire sizes and if the car is not daily driven get NT01’s or Cup2 tires and get a aggressive street/track alignment with not too much toe in.
Last edited by 03Zcrit; 10-23-2018 at 05:04 PM.
10-23-2018, 05:32 PM
#5
Thanks for the responses. I decided to replace the tires with Michelin Pilot Supersports. I got an amazing deal on a set of OEM tire sizes since the tire is being phased out to the PS4. I will mount them next spring since winter is coming and my car is sitting outside currently. Afraid of cold weather cracking since I live in northeast. I also plan on getting a more aggressive alignment to improve the handling next spring. Can't wait till next spring to test out the car on autocrosses and drag strip.
Ultimate plan is a pick up a set of CCW rims in 18s sizes and mount with NTO1s or R888R. But will slowly progress on that goal since pricey and I still have a track modified S2000 to beat around on motorsports tracks.
Ultimate plan is a pick up a set of CCW rims in 18s sizes and mount with NTO1s or R888R. But will slowly progress on that goal since pricey and I still have a track modified S2000 to beat around on motorsports tracks.
10-23-2018, 07:53 PM
#7
Burning Brakes
That's that's definitely true, the fastest I've ever seen when I was autocrossing was 80 mph. Even base c6 brakes would be substantial enough. Also don't run race pads for autocross as they won't get hot enough.
Last edited by 03Zcrit; 10-23-2018 at 07:53 PM.
10-24-2018, 08:40 AM
#9
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If you are new to this I would replace the tires with something newer for safety, but not super sticky (NOT BFG rivals or Brigestone RE-71R, etc.). Those Michelins PSS should be OK. A low grip tire will allow the car to slide more and help you learn and refine your technique. Drive the car stock (with a proper alignment) for at least 1 full season before making changes. Sticky tires and go fast parts will make you feel like a super hero, but can also mask a lot of bad habits. Once you have learned the proper driving techniques you will be able to take full advantage of the go fast parts you add later on. I know, its not what everyone wants to hear but it will help make you a better driver in the long run.
Last edited by Kubs; 10-24-2018 at 08:42 AM.
10-24-2018, 01:11 PM
#10
If you are new to this I would replace the tires with something newer for safety, but not super sticky (NOT BFG rivals or Brigestone RE-71R, etc.). Those Michelins PSS should be OK. A low grip tire will allow the car to slide more and help you learn and refine your technique. Drive the car stock (with a proper alignment) for at least 1 full season before making changes. Sticky tires and go fast parts will make you feel like a super hero, but can also mask a lot of bad habits. Once you have learned the proper driving techniques you will be able to take full advantage of the go fast parts you add later on. I know, its not what everyone wants to hear but it will help make you a better driver in the long run.