I know you mentioned track days but honestly you're better off going with smart pad choice that gives will absorb a nice level of heat and abuse. Obviously you'll want a compound that won't have you replacing rotors after each event. Basically, you're better off playing with pad choice until you find the right one. On a road course, good pads and hoosiers will get you far And as Ted said, it's all relative to how much power your car makes. A TII with 350 horses will need more fade resistance than a 250 hp TII of the same weight. The higher power car will hit higher speeds on the straights or even in cornering which will make more heat/stress on your brakes.

 

okay Ted, i'm sorry if i pissed you off. actually, i kind of thought that might happen
i was merely throwing some suggestions around. and it's not like i don't drive my car either. i think trying to cool down the brakes when you are idle is valid, because if you have ever done any autocross, after lots of runs and sitting still in between, you start to notice fade. remember, brakes only get proper cooling when the car is moving...
as for the oil cooler, yes, i know the idea is kind of far fetched...but i figure if rubber or steel brake lines can hold the pressure, can't the hard metal lines of a oil cooler? well, maybe not. but i think that's not the problem. the problem is that the brake fluid system does not circulate...whatever, enough of that idea i guess.

oh, you also mentioned a built in proportioning valve. does this mean the car comes like this with the stock system? have to check out the FSM i guess...

 

What?!?! How exactly do brakes cool more when the car is moving (and the brakes are being USED at some point) then when the car is sitting parked/idling? If anything, the air traveling through the ducts keeps the brakes at consistent temps. If you notice your brakes are fading after a few runs at the autocross try a set of pads with a different heat range. Get yourself some racer tools like a heat probe. Then you can find out at what temps your brakes start to fade and go from there...also, it's a great tool for taking tire temps and figuring out your alignment.

 

yeah i know, it's called a pyrometer. it'd be nice to have one, but don't have the money for one right now. definetly a useful tool though...

but maybe i wasn't clear. of course the brakes are going to get hotter when you use them, which is, yes, while you are moving. i was just implying that the brake ducts only work when the car is in motion and you have air going through them. driving at, say, 30mph while not using the brakes cools the brakes more than sitting still. plus, you get more heat soak from the rotor to the pads, and then to the brake fluid, if you are sitting still...

 

Again, we go back to the above. You don't need a big brake kit unless you're on track. Your tires can't handle any more braking force than you can already provide now. All you'll get with bigger brakes is better modulation and more heat absorption, which you shouldn't be needing on the street in the first place.

If you're fading the brakes now on track, look to race pads and a set of ducts to deal with the fade. Unless you're running slicks like Pitchblack is going to, stock size brakes are fine. Don't believe me? Fine, here's vid from Buttonwillow, I ran a 35 minute race pushing as hard as I could, dicing it up with another FC. http://para.noid.org/~silkworm/bw-040304-race1.wmv and http://para.noid.org/~silkworm/bw-040304-race2.wmv

RETed is absolutely right about the pressures involved. You're far better off dealing with the heat by ducting air to the rotors themselves, which is where most of the heat is stored. Remember that a brake system isn't a loop, fluid doesn't circulate like oil or water lines. You gotta evacuate the heat from the systems generating the heat, and buy the proper fluid to handle the heat you can't evacuate.

As for the sitting idle issue, yeah, ducts (and vented rotors for that matter) are only really going to work while moving. OTOH, properly ducting the brakes while on course, as well as proper brake pad selection should minimize the amount of impact this has, as the ducting will keep overall temperatures down while the brakes are actually generating heat, and the pads selected will be able to deal with the increased temperatures in any case.

PaulC

 

I maintain 20-25 of these cars daily. Believe me, they go through rotors plenty when they are driven more than one weekend a month. You do make a valid point with the weight vs. brakes setup. Cost is another factor with these cars. Two piston btw.

I didn't mean to insult with the bling-bling but just trying to make a point.

Unless you have tons of power (400+ for example) that will get you very high entry speeds into corners and punish your brakes as a result, better pads and ducting will suit most everyone fine. The several thousand dollars could be better spent elsewhere.

Your money...

 

i maintained plenty of formula mazda's, too (i didnt feel th need to say that i worked with them because i didnt want to come off as cocky), and NEVER swapped rotors. rotors were swapped, but i never had to, and that was working with the cars full time for about 8 months. i saw the same guys go out and do numerous 30 minute sessions regularly. we never had a problem with the rotors. brake pads were replaced, checked, or shim'd a lot, but rotors weren't.
what happens to your rotors? ours stayed looking good.
i can't speak about the "pro-car" (did they ever name it?). some people call it a formula mazda, i believe, but its above (as you know) the formula mazdas. i left before we ever got those. they're badass looking, though.

 

AP Racing/ Brembo and Performance Friction, the best in both their respective catergories maintain these claims.

AP and PF come do seminars twice a year for us. I have also talked to Brembo reps at the track on occasion. We also employ ex-Indy/ Lemans/ Trans Am / Nascar mechanics and drivers. All agree.

They do help crack your rotors and eat your pads faster though if thats what your looking for. Plus they look cool, thats why I have them on my vert.

My vert has almost 400 rwhp now and I still only run better pads and ducting (plus those stupid rotors). The car has seen lots of track time, but not with the new engine so we'll see how it does in the braking dept.

Mazdaspeed sells good rotor ducts made by AWR that can be had for a decent price with their contingency program.

 

its always good to challenge someone who can back up a claim. i learned in brake class that the slotted/drilled was to prevent gas fade (as opposed to the cooling aspect many people seem to think). how well do they work? well i dont know. i must say, you provide a tough arguement (assuming youre telling the truth and i believe you).
i've heard of the drilled cracking, but read that the slotted are better about not cracking.
so who makes a regular rotor for our car that you would recommend? factory size, of course.

 

Basically our cars see as much track time in a week as most others do in a month. Over a race weekend some cars may see as much as 10 hours of track time. Lots of work to keep up with.
During a normal week they'll see about 3 to 4 hours of track time.
Your right though, a few 30 minute sessions occasionaly won't put much wear on the rotors.

One thing I've never been accused of is not being cocky

 

your mentioning of working with the cars was necessary and came off casual. when i originally posted, i never saw it needed to say that i worked with the cars. most people dont even know what a formula mazda is, though (as i didnt before my friend took me to the track).
yea, 10 hours is a lot. i worked mostly with "well-off" customers who liked to have fun in a very fast car. we did go to races, though. none seemed to take it too seriously, but at the same time took pride in the racing. it was a fairly happy medium.

 

Your right about the intent of the slots and cross drilling along with making them look better for a consumer public. Better pads will cure this. Some will argue the slotted rotors even give you more initial bite, but that is probably in their head as the basic tests I did that anyone can do didn't show any improvements in any catergory and I don't know of any tests out there that contradict this. Hence my statement based on experience and the claims of a few reputable manufacturers. I have used both slotted and cross-drilled over the years and yes, the slotted are less prone to cracking than c-drilled but more so than stock. This is in my own personal experiences along with many others. Still doesn't mean we're right though.

Forgot to mention that Carroll Smith also used to give seminars 4 times a year and someone would always inevetably ask that this question.

I hear Mazda makes a pretty good rotor for our cars that can even be had at racers discounted prices with their contigency program

 

i always wished that working with Texas Austosports would get me a discount at Mazda. i mean, they're mazda sponsored racecars with some genuine mazda parts; why not?! i do know a guy that is a master tech at mazda that said he would get me anything i wanted from mazda with his discount. i have yet to take him up on that. only thing i've asked for so far was new rubber exhaust O-rings, but he never remembered. and then i'd forget to call and remind him while he was at work. a vicious cycle.

 

I have a BIG problem when people start talking about stuff that can KILL you.

There's been a LOT of misinformation in this thread, and I highly recommend to go read the Brake Handbook by Fred Puhn.

http://www.amazon.com/exec/obidos/tg...books&n=507846


-Ted

 

This has been one of the highly debated points of the Wilwood calipers.  I've been running this set for over 4 years, and there is no degradation in braking performance since they have been installed.  This is basically the prototype kit that K2RD developed.


I can't really comment on this directly; my comments were made in general.  How popular is this conversion for the FD guys?  I've never really heard about it till now...


-Ted

 

It looks like this thread has turned into an FM thread, which is not even close to brake applications on a 2500+ lbs. FC3S chassis putting down anywhere from 150hp to 300+hp at the wheels.

Brakes (mainly brake rotors) take the most heat under deceleration with prodigious use of the brake pedal.  After releasing the brake pedal, brake (rotor) temps drop dramatically unless something is drastically wrong.  Front brakes do anywhere from 70% to 90% of the braking force on the vehicle.  Most of the theories we are discussing is for direct application for the front brakes.

If any of you have serious track experience under your belts, the stock brakes + Hawk Blues (or equivalent) will produce a very competent track vehicle in terms of braking performance.  FC's producing over 300+hp at the wheels and / or high-speed tracks with extraordinary high deceleration zones (Laguna Seca T2, Thunderhill T1, etc.) in succession can overwork this combo, but brake ducting can help a lot.  Brake ducting is one of the most easiest and cheapest "tricks" to improve brake performance.

Big brake kits are not necessary.  About the only guy that I know that uses a big brake kit to it's full advantage is tims, as he runs a Super Unlimited in NASA Pro Racing.  You might want to talk to him about big brakes if you're serious about getting one...


-Ted

 

i understand that, but when you talk like your nose is stuck in the air, you just come across as an ***. there's a difference between correcting someone and being rude about it. "Leave the racing stuff to the professionals." jesus man, your word isnt that of a god. do you realize how cocky that sounds? go write a book.

as for turning into an FM thread, i merely made the point that some racecars use brakes that would be less than suitable for some street vehicles, yet work fine for racecars that reach higher speeds than most cars on the track. i wasn't saying "downgrade your system because thats what these racecars use."

 

I never meant to imply such attitude.



-Ted

 

Recent thread in the Suspension section...

https://www.rx7club.com/showthread.p...hreadid=321021


-Ted

 

damn. 30$ for that book.

 

knowledge is power! and sometimes that costs a few Hamiltons. (yea yea, go check your bills)

 

I spoke to one of the stoptech guys via email a while ago and he had mentioned if approx 10 or so individuals were interested (financially committed), they'd take production of an FC setup into serious consideration.

On another note though, I like the new monobloque design PF and Endless are now using. Although, I can't justify an upgrade quite yet. The current setups working well.

 

Well lets say that you do autox and drift pretty often what kind of brake system would you apply, i have a 86 base that i did the 5 lug swap to (including 87 gxl brakes) and rite now im saving for a 13b-re, would the brakes i have right now be enough to stop a 300hp car? or is there a better rotor/caliper upgrade that is affordable? links would help :P

 

Stock brakes with appropriate pads will serve you very well for autox and drift, you never get going very fast compared to circuit, where the stock brakes still hold up well with the right pads. I had some EBC greens on mine for a while, worked awesome for autocross, it was like you hit a wall when you stomped on them. Don't even think of taking EBC Greens to a circuit though. I tried it and it cost me a set of front brake rotors when it ate through the pads and into the backing plate in about 8 laps of VIR full course.

 

what if you had 17" rims would the stock brakes be able to handle the increased rolling mass?