82transam

iTrader: (18)

does anyone know where I can get slotted/drilled brake rotors for my 83s? Also I want to get better calipers too. Does anyone make a 4 piston caliper, or at least 2, stock is 1 piston right? TIA

riffraff

you can get the rotors from mariah motorsports or rx7.com.. no idea on the calipers.

DJ!

calipers im using 4 pot off a s5 turbo and making my owner brakets to mount them onto the stut.

genrex

No idea on the calipers.. just want to say that replacing the stock flex brake lines with s/s braided brake lines will make a big difference in braking power..

yayarx7

on my autocrosser/daily driver I put high perfromance pads (ferodo, then bonez) on all four corners with new brake rotors, then ss lines. That, along with my stickey yokohama a509's, seemed to be quite good enough for a street car. Never had ANY fade and never failed to lock em up.

I think that anything else would be overkill on a street/autocross car, but you might need more on a track car.

Pele

iTrader: (28)

Locked up all four wheels at 45 MPH on stock brake rotors, Cheapo parts house pads (AutoSpecialty... They come in a gold colored box... Squeak like mad.) and I had Kelly Chargers on the front and BF Goodrich Control T/As on the back.

82transam

iTrader: (18)

yea yaya I'm sure it would be overkill. But overkill is my middle name. Everything I do to my car has to be the best possible or its a waste of time/money in my mind. Hmmm maybe I need help. Naaa this is America, bigger is better, everyone needs drilled slotted rotors and 4 piston calipers. Thanks all for the info. L8R Peace

peejay

Cheap NAPA pads on stock brakes... no fade, great stopping power once heated up.

SilverRocket

I've heard that cross-drilling rotors as small as ours is pointless and doesn't help anything. I got some Hawk HP+ pads last year, with otherwise stock brakes and Motul 600 fluid, and they're just fantastic.

I don't see any reason why a street driven FB could possibly need more braking than stock brakes in excellent condition w/ good pads can provide. Remember how light our cars are; all that 4-piston stuff is overkill for an FB IMO.

peejay

Fade resistance is directly related to how much mass the rotor has to absorb heat.

Cross drilling reduces mass.

You do the math!

Directfreak

iTrader: (2)

Agreed. Unless you a runnin' some SERIOUS HP like AJC13B or something.

jeremy

iTrader: (1)

absorb and SHED heat. cross drilling opens more surface area exposed to the air so the rotors can shed heat better, thus reducing heat soaking, thus reducing fade by boiling the break fluid. it also allows air to easily flow thru the center of the disk, further aiding in cooling. slotting is used to expose surface area also but is mainly there to "shave" the pads so you always have fresh pad showing. it also means you change them more frequently.

peejay

You don't shed heat while braking! Unless your brakes really, really suck, you will be decelerating so fast that any cooling breeze will be minimal.

If the mass of the rotor is reduced, then the rotor can not absorb as much heat before it's soaked and the heat gets to the calipers. While what you say does have some merit, the problem is the calipers are not ventilated! They're not going to cool off as easily down the straight.

Another thing to think about is that the cross-drillings are perpendicular to the axis of rotation. Very little (if any) air will flow through. Even spoked bicycle wheels with their big, wide air gaps take on the properties of solid disks when they spin fast enough! Do you really think airflow is going to even see the little tiny holes when the rotors are spinning at 800-1600rpm?

jeremy

iTrader: (1)

yes, because the air is turbulent. the heat of the rotor affects the heat of the caliper too. if you want i'll draw up a mock diagram of airflow possibilties at 60 mph in the wheel well and around the caliper. the surface area gained is far more then the little bit of mass loss. this of course can be gained back by increasing the disk diameter, which will not have to ba as much since this will also increase the lever arm. anything that makes heat releases it. the part of the disk at the bottom will be slightly cooler, not by much though. the cooling effect happens after the braking. if you have brake fade after using the brakes once, then stop living on a mtn top. i was going to say that ventilaton will help a ton and two fold with crossdrilled but i figured i shouldn't post a book. when creating a venting system, it is very beneficial to aim the stream perpendicular to the rotor. also open rims will help in opening up a stream of air. as for the air passing it, yes like you said a certain speed the break point will pull further back. so for all of those driving 150 and braking constantly it will be a problem but not at the slower speeds. mine will need more help because i have the old waffle type rims which allow little airflow through them. removing the shield and rigging up some ducts should help tremendously although is probably over kill since i've only faded brakes once on a 10 min hilly backroad run. but it will help keep the rotors from warping over time.

peejay

I've faded the stock '80 brakes, oh let's see, how many times.... NEVER. Including a series of 30-100-30 dashes, accelerating full throttle and then nailing the brakes practically with both feet. Just trying to see how good the new brake fluid was.

mar3

iTrader: (8)

I have previously faded my brakes ('80) in extreme-anger street driving with semi-metallic pads and no cross-drill. That's when I decided to go to the cross-drilled house which solved that problem. Here's a link to throw a little fuel on the fire about why you cross-drill...


the real reason you cross-drill...or not??

It should be duly noted that most of today's modern brake pads no longer exhibit the out-gassing characteristics that prompted cross-drilling, but how do you know that unless you test 'em in a lab? Let the beatings begin...

jeremy

iTrader: (1)

oh i see my reasons aren't good enough. you can just take your gassy pads and........

mar3

iTrader: (8)

Vampire!!

jeremy

iTrader: (1)

yeah, my brake fade was in my camry and it was an all out rally down a very hilly backroad, becoming airborne a few times with a 250 lb passenger and 2 fully loaded tool boxes in the rear. it was so smooth i didn't realize we were airborne until we landed coming down the other side and the brakes squealed. i haven't even driven my 7 yet as the gunked carb is in a trillion pieces soaking in carb cleaner/gas right now. you have to be driving insane on public roads to overheat the brakes and it will take more then the 30-100-30. like i said it was right as we were a few turns away from the junkyard and then i almost couldn't get it slowed to turn in. the fluid was boiling as the peddle went to sponge. of course that was also in a camry. but its 91 technology looks the same as my 79's minus the "safety" way of routing the line for full failure prevention. single piston fronts, drum rears. disks look about the same size and the drums were larger on the camry, but it was also 400lb+ heavier. especailly with chunky and the tools.

jeremy

iTrader: (1)

doth my food mock me? for i will not sucumb to its taunts as it will be dealt with upon a later date.

82transam

iTrader: (18)

OK, so it seems that most of you agree that it would be a waste of money to upgrade the brakes but if i were to (completely hypethetical of course) which would be better for agressive street drivng? slotted or drilled? Thanks Peace

peejay

Better would be neither. They don't look as blingy but so what?

Cross-drilling is only really used in motorcycles (and now bicycles!) anymore - they have solid discs, everything is out in the open, and it helps remove water and road grit (and mud and goo, on bikes) from the rotor.

jeremy

iTrader: (1)

cross drilled as your pads will last longer and it will be blingier <-- i copyright that word

82transam

iTrader: (18)

correction it will be the "blingiest" Ha now I copyright that word, now what huh??? J/K
Thanks for the input dude

mar3

iTrader: (8)

My cross-drill rotors eat my pads for lunch. I'm having to change a little over a year each time. I'll post a pic of what they do to "dustless" pads Satyrday nite before I hit the 'Case with a buddy. Mind you, this is all regular street duty with the occasional drag down to 20 from 90 just to feel the belts across my chest...I'm gonna see how Hawks fare against them next....