Just got back from Buttonwillow and im getting this loud groaning sound from the front when I brake. My steering wheel doesnt shake at all, but I do get the groaning and also my brake pedal doesnt feel as stiff as before. I'm faily new to tracking so I did use the brakes quite a bit. Btw: I had fresh ATE super blue fluid, hawk HPS, and a 13in 2pc brembo kit. I hope I didnt warp the rotors as they are very expensive replacements. one of the reasons I went with a BBK was so that the rotors would be less prone to warpage. What you guys think, warped rotors? Could I have maybe cooked my brake fluid as well? Thanks

If your steering wheel doesn't shake when you apply your brakes, then your rotors are most likely not warped.

So - what is the sound? Most likely pad transfer where the compound from your pads has moved over onto the rotors. But you should be getting a little shimmy with pad transfer. I wouldn't worry about it too much. Also, the pedal feel might be in your mind, but if you did get the brakes VERY hot, then you may have bioled the fluid and this could result in poor feel. Pretty easy to flush it though.

By the way, BBK's don't mean you won't warp the rotors. I once instructed a guy with a 1996 993 Turbo S who had put on a new $5000 BBK the week before our event. He warped his rotors at Cal Speedway in one track session. Poor braking technique can warp rotors fast. Brake cooling can help a bit.

Hope this helps.

I've noticed some street pads just seem to do that. I think it is coming from glazing the pad surface, so you get some low frequency vibrations. As with most "bad things" that happen when using street pads on the track, it'll probably go away after a week or two of street driving.

A lot of people mistake uneven pad deposits for warped rotors. I even did myself. Towards the end of a trackday back in December I was getting the "warped rotor" feel with my brake pedal shuddering. After I got home and put my stock pads back on, after a few days, it went away.
Here's a good article about rotors and pads.
http://www.stoptech.com/whitepapers/warped_rotors_myth.htm

Sounds like you cooked your fluid (soft pedal). You may also have a bad wheel bearing (noise). Heating up the brakes enough to cook the fluid is bad for wheel bearings. You also likely have pad transfer which will cause shuddering.

I've cooked ATE on a couple of occasions. I now use Motul600 and I replaced my wheel bearings last year. I'll be adding ducting soon.

Jay

Thanks so much for the responses guys! The sound isnt really that bad, I'm not sure how to describe it. Best way to describe it is when braking, it makes a progressive groaning sound from loud to soft as I slow down. I hope its just pad deposit and will try cleaning it tomorrow and re-bedding. Also I was hearing a metal on metal contact sound from my front brakes as well after a hard session. But after the brakes cooled down, the sound went away. Thought I wore through my pads at first, but they looked hardly worn when I check them out again. Anyone know what it was that I was hearing? I thought it could have been my dust shield hitting the rotor after expanding a little from the heat? Well, I'll probably try running a race pad next time.