Apparently I did - look at the last line under post #16... the OP was asking for advice (follow-up question).

 

So I just jacked the car up in the front. Spun the wheels. I could clearly hear the rotors hitting the calipers on both sides. It's not a constant rubbing, it happens once with each rotation and is clearly audible. Seems like warped rotors to me!



I had so much fun at autocross that I know I'll be doing it more. It may be time for an upgrade There's no point of buying the same rotors and just warping them again at the next event.

I'll probably order one of those air duct kits too, a guy there had one on his C4. Certainly couldn't hurt to have some air flowing through there.

Nope, tires look good! Well, as good as Sumitomos can be

I've heard it a million times, trust me. It's not stopping me!

I just used the jack, it held up. I need to get one of those




So it appears to be warped rotors. I plan on continuing to autox, so I think I should upgrade. Research begins now. Any suggestions?

Edit: no arguing allowed, only brake advice, thanks!

 

If you're looking for rotors, try Brakemotive, they are a vendor here and have great prices. I installed them on all four corners of my vette last year along with pads and couldn't be happier. I went with the drilled and slotted kind.

 

Ok, for staters my car has the small 12" brakes on it. I've NEVER warped them running auto-x. I've boiled FRESH DOT 3 brake fluid however at an auto-x. I'm running DOT 4 Motul RBF 600 now, no issues.

The brakes do get hot, a couple tips. Don't sit with the brake on in the staging lanes between runs. If you have to, do it very lightly, and let the car roll forward a little once in a while, every minute or so.

If your between heats,I usually just shut the car off, and leave it in gear. NEVER set the parking brake with hot rotors.

Over torquing the wheel nuts can cause brake rotor warpage as well. 100ft-lbs and no more.

You don't need the cross drilled and/or slotted BS to run auto-x. Or even HPDE or track events. Many a race car run just plain vented cast iron rotors.

Heck, for auto-x you don't even need the Hawk and whatever pads. The brakes just don't get super hot at a typical auto-x. Good pads are a much for track use and don't hurt for auto-x but you don't NEED them.

Ditto on the brakes cooling for auto-x, you really don't need it.

Warped brakes come from: Too hot then sit with parking brake/brakes on.
Over torqued wheels
Too much lateral runout in hub
Too much lateral runout in rotor
Too much thickness variation in rotor
Brake pad deposit build up on rotor see above about thickness variation.

 

Sorry to hear, glad you got it fixed.

I'd get the fluid in the calipers changed

The pistons may be hanging up.

I'd try that 1st before anything else.

 

Advice, yes. That would be on the problem with his car. Not "parental" advice.


OP, Your calipers aren't hanging up, b/c you could turn the wheel when you jacked it up. Still flushing brake fluid is good PM and should be done annually.

If you're looking to upgrade, look for well priced, take-off sets from newer cars, like the C5. We don't know you budget, but I did a C5 upgrade for <$500. I got rotors, calipers, brakets, the adapters, HP+ pads and it made a huge improvement. For <$500, it was a smokin' deal.

The alternative is to buy the CHEAPEST rotors you can get, and treat them like disposable items.

Honestly, I can't believe that you warped rotors in auto-x. Are they worn really thin? Were you "two-footing" it?

 

Thanks again for the advice Rubie. Between runs I turned off the car, opened the hood, and put it in gear. I also have the little 12 inch rotors. I think the rotors could just be very old and weak, I was surprised that it happened too. I think cheap replacements with a little home-made ducting along with proper driving habits would work, what do you think?

Also, I checked the torque on the lugs, seemed to be about 100.

The wheels turned pretty easily, at least the fronts. I didn't jack up the back. I am definitely going with a better brake fluid and power steering fluid before next time though.

I think they were just really old, they could very well be the originals (car was babied before I got it). I'm considering the C5 rotors but I'm not sure I need to do that. They would be nice though! How did you do it for that cheap??

 

Vinnie, the best thing you could do is walk around and ask questions of the guys at the event..See what there using and how it's working out for them..There are also quite a few guys on here with good advice..As you can see from the posts on here, opinions differ greatly....You can't get any better advice then from the guys that autocross on a regular basis........WW

 

I scanned the classifieds until I found some for a good price.