Joshboody

I typically always drive and track with traction control OFF. Sometimes I do leave it on on the street, but never noticed an issue... until the other day. Leaving the track on the hwy seemed like the rear brakes were on and display said traction control active... turned it off and the car released forward. Prob was reduced engine power rather than brakes. Very weird and FYI: I guess square can cause an issue.

burnsie629

I have heard that can happen. I have just started using a square setup for track and auto-x, but haven't had it happen, yet. I do sometimes forget to turn it off on the drive to and from, but have not had anything happen and maybe it won't....we shall see.

1badtantrum

Wheel speed sensors are providing data to EBCM. EBCM expects a rotation speed difference between front and rear in staggered wheel/tire cars (C6Z06 for instance). I think the recommendation is to maintain a 1" diameter difference (larger in rear) between the front and rear tires for the EBCM to operate in the tested conditions. I'm not sure how exactly square your setup is. For instance, there is a fairly common Hoosier tire square setup (18") that many C6Z track cars use. The rear 18 is about 1" larger in diameter than the front.

ZedO6

C5 or C6?

Sox-Fan

I ran square tires on my C5z. I'd air the tires up or down during the course of the day and if I forgot to reset them properly after they cooled I'd get complaints from the car when I'd leave a venue and hit the road. As long as I put the pressures back to where the rear was a little higher than the front the car never gave me a problem with traction control on the street.

kmagvette

FWIW - I used to run square on the track for many years; depending on tires, sometimes I still do. I always run square on the street and for my rain set-up. Never had any issue whatsoever. Car is a C5Z. I always shoot for equal pressure and never went out of my way to inflate anything more than the other. Street tires are all equal too.

SouthernSon

I totally misread that. I was reflecting back to the time a vehicle parked it in front of me at the start finish line. After a 200 foot skid mark the tires were mostly just elliptical. But, for the matter at hand, I have run 18" square for several years on a C5Z (03) and have never had an issue. Always A/H off, though. As far as the limp home mode, I only had a problem once when the throttle body motor went belly up.

Gordy M

Several times I have run a square set up without any problems, last year I put 2500 miles of street, heavy autocrossing (200+runs) and a couple of HPDE's. However, each time I change tires sizes I also go in and change the tire size diameters for the speedometer--bi-directional controls.

Bill Dearborn

I ran an equal diameter front and rear set up on my 97 and C5Z. TC wasn't an issue on either. However, I do know some people running a square setup who had issues with their C5Zs when on the highway driving in the 70 to 80 mph range. I believe the difference is in which particular EBCM is mounted in the car. EBCMs are a combination of digital/analog circuitry and can have some variances from one unit to another. What sets one off may not set the next one off. When you are running a square setup you are right at the edge of the tolerance band so slight differences between units can make a difference to how it reacts.

C5 traction control tries to reduce perceived rear wheel slip by first reducing engine torque but if that doesn't work it applies the rear brakes. I proved this on both my 97 and 03Z. I took the stock wheels and tires and swapped them front and rear and then tried to drive both cars. They wouldn't move without TC being turned off. I lived on a hill and when I put the cars in neutral and tried to coast down hill they both came to a stop because the EBCMs applied the rear brakes to stop perceived wheel spinning.

Bill

Joshboody

This was the first time I ever noticed in 2yrs being square with about 5k/yr street driving... but TC is typically off. Prob was the pressure diff.