name for me a single production car that will not toast its brakes from a 120mph stop, under 100k.

I will fade my race pads under that condition.

 

you need better race pads mike i can almost hit 120 at thunderhill and thank pmu after turn 1 every time. but actually youre right, im getting ferodos soon heh

 

not to discount the possibility, but again i highly doubt these vibrations are caused by warped rotors for any reason. your rotors dont warp just because the rotors are at a higher temperature. they can warp due to cold or hot working (for example thermal shock). and for a road car (even when racing) to warp its rotors is something that rarely, if ever, happens.

 

Huh????????????

 

holy crap which PMU are you using? to do a 120-0 stop

I actually fade my carbotech XP10/8 on my s2k on warmer days...and that is on street tires. I may need to step up to 12/10.... =(

the XP10 is rated for 1650F/900C....

I believe stock G pads will handle half that... 400-450C, although I havn't seen a solid spec for it. They will fade on a full ABS 60-0 stop.

OT: Which groups do you run with? I'd like to do Sears Point/Infineon and Thunderhill soon.... a few nor-cal trips are in order

 

yah so in order to even get the rotors to a really high temperature for warping to even be possible you would need race pads (street pads will not make the rotors even glow). the oem pads, like mike said, will be good for one solid braking and then proceed to disintegrate (i think the term is gassing out).

i used pmu b force. a good street pad, stats say it handles up to 500C. i keep forgetting to bring my IR temp gun with me so i dont know if this is conservative. the coef. of friction does drop as temps go up though. so im going with ds2500, claims are MOT of 540C and constant coef. of friction up to that temp. (yes, im a wimp who keeps using street pads, but the evo crowd swears by ds2500)

OT: would love to do infineon, just kind of expensive. speedventures rarely goes to thunderhill, wish they went more often because its my favorite.

 

what i meant was in traffic if you are behind a car with the cruise on, it will continuously tap the brakes to maintain the speed. I dont know, I feel one good stop from 100mph + warps these rotors, and yes i am sure that they are warped. I know my way around cars.

 

Warping is very unlikely. It is caused by one of two things: uneven heating, or uneven cooling.

Uneven heating is nearly impossible, as the rotor is spinning, and the braking surface is pretty much the entire rotor's surface.

Uneven cooling could be a culprit, but only if you come to a complete stop and do not move for a bit.

Refer to :

http://www.stoptech.com/tech_info/wp...rakedisk.shtml

And yes, they DO have an interest in selling you more rotors.

If you an provide a picture of your warped rotor, I'd be more than happy to retract my statement.

Simply resurfacing/turning a rotor does NOT fix warping, if that is what they did to make your problem go away.

 

i would suggest the OP a half dozen things that could cause vibrations before saying its warped rotors. pad deposits? try bedding brakes in again. how old are the rotors? perhaps they were mounted improperly (using impact gun to tighten lugs). were they turned? maybe the shop did a crappy job. if you brake hard and let go of the steering wheel, does the car pull to one side? perhaps your caliper pistons are sticking (failed piston boot). are the wheels and tires properly balanced? are the rotors mounted to minimize runout?

 

no, the dealer turned them, i torqued the lugs myself, the car only has 15,000 miles on it, symptoms started at 8k, they turned them [infiniti] and it was completely gone [vibration in the wheel] and no they dont pull to one side. this is a brand new car here. after running my car to 130-140mph and braking, its back again. I drive my car rather rough, push it to its limits regularly. its a sports car and im sad to see 14 inch rotors warp! i dont think its pad seating or caliper issues, its a brand new friggin car. I think these rotors are made in china, lol

you are talking like my car is 10 years old with 100,000 miles on it. These things dont happen to new cars btw. and the shop is infiniti, like i said, they warped before, were turned, and the braking was smooth. now its back, run your car to 140mph and slam the brakes. then youll see.

 

no, i know how old your car is. i also know how you drive it and its obvious you arent doing 130-155mph on the track. high speed braking requires a good amount of cooling to prevent pad transfer. the fact you said all was good after turned rotors pretty much confirms the problem is pad deposits. i dunno man, maybe i am missing something...

 

All right, ill give it a try, ill clean them up and see if it fixes the problem

 

just trying to help. if your rotors really are warped then turning them will not solve the problem. warped rotors are done and should just be thrown away.

 

well, thats all on the service tech, i rememeber when i took my car to the drag strip i broke an axle, i knew it was the axle cause i saw the boot all twisted around.

took it to the dealer, they changed my clutch, flywheel and pressure, and ODDLY that didnt fix the problem, so they then changed the axle.. lol

then i had the throwout bearing noise and muffler rattle, they hooked me up with a new muffler, new clutch, flywheel, pressure plate, and a new tranny. go figure.

 

They told you that because it is easier to tell you that than to explain what happened.

Warped rotors CANNOT be turned. They turned them to smooth out the surface due to uneven deposits. Warped rotors are not straight anymore and have no structural integrity.

Take ANY production (non-race) car, and go to 140mph, and slam on the brakes and come to a stop. You will fade the brakes. Period. No ifs ands or buts. I challenge you to find me a car that can do this.


If you are RACING a street car, then obviously you are doing things the car is not designed to do. Since you're an accomplished drag racer, you of all people should know that when you race, you find the weak point, and then make it stronger until something else breaks, make it stronger, etc etc etc.