Cal Club Autocross Forums

Hey guys, after copious amounts of runs this weekend at practice, I noticed that my tires were making an unusually high amount of noise on the drive back from Fontana. I've had this set of Z1 StarSpecs on my car for a few months now, but I've probably racked up about 120 novice runs on them (which means that I've beat them up pretty bad). I've only rotated them once, but the wear seems to be the same on the front and rear. In your opinion, do these tires need to be replaced, rebalanced or are they still good to go?

Here are some pics - any advice that you may have is greatly appreciated!

Ryan Young wrote:Hey guys, after copious amounts of runs this weekend at practice, I noticed that my tires were making an unusually high amount of noise on the drive back from Fontana. I've had this set of Z1 StarSpecs on my car for a few months now, but I've probably racked up about 120 novice runs on them (which means that I've beat them up pretty bad). I've only rotated them once, but the wear seems to be the same on the front and rear. In your opinion, do these tires need to be replaced, rebalanced or are they still good to go?

Here are some pics - any advice that you may have is greatly appreciated!

Toast. Surface at El Toro is a lot rougher than Fontana and your tires will most likely show its cords at the test 'n tune (or Saturday if you decide not to run it on Friday). Best to get a fresh set.

Tony

Can you have them flipped on the rim? Looks like your car wears the outsides due to a lack of camber. I would get a new set and save them for practices. Tough to say if those outsides will cord.

two different questions being asked in the "are they toast".

Tread-wear:
Depth looks OK. Outside edges look a bit over cooked. If the insides look better, flip them on the rims, and keep running them.
Heat-cycled:
Can't tell from pictures. That requires comparing times, feel etc., compared to new.

But you mentioned being a novice, unless money is no object.... I'd just flip them on the rims (heat-cycled be damned) and keep running them. Based upon the wear on the edges, I'd guess your still learning not to plow through corners... so keep using these to learn on as long as they will last.

JMHO, Craig

Craig Naylor wrote:Based upon the wear on the edges, I'd guess your still learning not to plow through corners... so keep using these to learn on as long as they will last.

I don't think it's fair to say that outer edge tire wear indicates improper driving technique, as you're not so subtly implying. It indicates a lack of camber.

The best driving technique in the world won't save the outer edge of the tires on a camber challenged car. (see avatar pic for an example of such a car --->)

Thanks for all the replies! I think I will take my runs this weekend on my stock wheels & tires, just to play it safe. The inner edges are in a lot better shape compared to the outer edges, so I'll probably try flipping them on the wheels & using them for practice until they are completely done. As for the wear pattern, I did max out my stock camber right before the ProSolo (it isn't much - maybe 2* on the front), but I'm pretty sure that my driving technique is the main cause of the tire wear!

Ryan Young wrote:Thanks for all the replies! I think I will take my runs this weekend on my stock wheels & tires, just to play it safe. The inner edges are in a lot better shape compared to the outer edges, so I'll probably try flipping them on the wheels & using them for practice until they are completely done. As for the wear pattern, I did max out my stock camber right before the ProSolo (it isn't much - maybe 2* on the front), but I'm pretty sure that my driving technique is the main cause of the tire wear!

I think the tires are safe and should certainly last throughout the weekend. I would just have them flipped beforehand. No use wearing out your less grippy stock set-up. If you are concerned about cording, you could always bring your stock wheels in the STi. You can borrow my jack and tools if you need to change them on site. What pressures are you running?

Rick

Jeff Stuart wrote:I don't think it's fair to say that outer edge tire wear indicates improper driving technique, as you're not so subtly implying. It indicates a lack of camber.

I think it's quite fair to consider that a new autocrosser is overdriving their tires. Better to not-so-subtly imply that it's their driving (and with a newbie, it usually is) than to have him chasing car setup pointlessly.

Richard Jung wrote:You can borrow my jack and tools if you need to change them on site. What pressures are you running?

Rick

Thanks Rick! I usually run 38 PSI all around.

Do you have a BIG front sway bar? That's the typical Suby bandaid to help preserve what camber you do have.

Mako Koiwai wrote:Do you have a BIG front sway bar? That's the typical Suby bandaid to help preserve what camber you do have.

Nope, I've just got the stock 21 mm that came with the car. That may be something worth looking into - thanks for the tip!

Ryan Young wrote:

Richard Jung wrote:You can borrow my jack and tools if you need to change them on site. What pressures are you running?

Rick

Thanks Rick! I usually run 38 PSI all around.

Bring those front pressures up with no front bar 42 psi at least to about 45psi HOT the car will respond better on turn in. And Craig is right, i can tell that you are over driving Into the corner .

Camber will only help a little in a subie , You have tons of weight past the front axle , no matter what you do alignment wise you still have to be aware of over working the fronts especially on entry.

Mako Koiwai wrote:Do you have a BIG front sway bar? That's the typical Suby bandaid to help preserve what camber you do have.

YES a big front bar will On Entry and in the slaloms, you will get tons of mid corner and exit push. I had a 29 mm front it helped, but i now have the rear bar.

Entry is slower but mid and exit are much better in my opinion.

Still getting the feel of the car though.

They are still safe to run and will be faster than the stockers. Get 'em flipped, or at least use the rears in the front, don't blow 2 points events on the crappy stock tires.

Tom Denham wrote: Bring those front pressures up with no front bar 42 psi at least to about 45psi HOT the car will respond better on turn in.

Thanks for the info, Tom! I'll increase the pressures this weekend and see how the car responds. I ended up flipping the tires around on the wheels - I'll bring my stock setup with me just in case anything happens!