930 brake upgrade, first generation

[Bill Verburg]

Listen to Thom, please!!

If you do anything his setup '78-89 930 f/r is the one you want. The big reds are overkill unless you have a heavy car that is raced hard and long.

You do not want to move any front caliper to the rear unless you want bias problems. Similarly do not do only one end of the car.

You do not need floating rotors(though they are nice for race use!). Use the one piece '80-89 930 f/r rotors, as long as you have a turbo flared car.

Some of the '75-77 930s already have the correct 3.5" mounts on their trailing arms in addition to the 3" mounts used by the existing calipers, look!

You should also plan on using the '78-89 930 m/c. Though not strictly necessary it is a very worthile upgrade w/ 930 calipers

[lendaddy]

Thanks guys! I will do the MC, fluid, pads, etc.. before I move on. The calipers were rebuilt about 4 years ago. It sounds like you guys have it down. Thanks.

[aseem]

Originally posted by beepbeep
930 78- brakes are perfectly fine. They are actually upgraded 917 brakes. Unfortunately they are quite pricey, even used. floating 930 rotors are mucho $$$...

Actually, the floating rotor is not expensive, I paid £60 ($100) per for 78-80 floating rotors. The "floating disk bell set" or disk clamps on the other hand are insanely so. Expect to pay $1000 for these. Here are aftermarked items from Ninemeister

My Porsche dealer adviced me to upgrade to 81- 930 brakes, as these are not floating, and have the bell and rotor integrated. Seems that 78-80 had the floating brakes, and 81- was non floating. I'm not familiar with the 77 design.

lendaddy
I agree with widebody. Do an upgrade. My 80 brakes had terrible fade on the track, and they were wobbling my stearing wheel like crazy. Scared me, and I just had to coast into the pit.

Changed the rotors, kept the old (and corroded bell set), new Red Stuff pads, and new ATE Super Blue fluid. They are now very much improved. Wish I changed the lines at the same time. Still have a tendency to sprongy feeling. Well, its gonna cost me an extra quart of Super Blue.

When discussing brake lines, some people advice against steel spun lines, and say to go for OE rubber lines. Reason: Steel spun lines has teflon liner that can burst after as they grow older Shure, they are used by racing teams, but they change brake lines frequently.
Any opinions on this out there.

[lendaddy]

I know it sounds a little stupid maybe, but shouldn't I be able to lock up the brakes? I mean isn't that the measure of the systems power? Not that you want to but you should be able to right? After that it's a matter of modulation and feel I would assume. Hmmm, am I alone in this area? Can you guys lock them up?

[beepbeep]

You should always be able to lock the brakes if you press hard enough. Frankly, i think Big Reds in front are good solution as price is roughly the same compared to 930 brakes.

[ChrisBennet]

Originally posted by aseem
Actually, the floating rotor is not expensive, I paid £60 ($100) per for 78-80 floating rotors. The "floating disk bell set" or disk clamps on the other hand are insanely so. Expect to pay $1000 for these. Here are aftermarked items from Ninemeister

Asseem,
That's a good deal. I wasn't aware of an aftermarket floating rotor. I bought my last set for around $250. Discount parts places have them for over $300 and the local dealer probably wants over $400. I had VCI supplied Coleman before this set and I don't think they wore that great.
-Chris

[don911]

Reeves Porsche and Sunset sell parts for cost +15%. Factory floating rotors cost just under $270 each from these places. Last week I bought a pair and paid $575 which included shipping.

$100 for factory floating rotors would be a steal.

[n8marx]

lendaddy,

Granted, this is not specific to turbos but rather a little anecdotal evidence to support Thom's recommendations. Last year I bought my '86 Carrera. Brakes seemed okay but not stellar. I could lock 'em up but barely. Over the winter I rebuilt the calipers, replaced the rotors with stock components due to wear and cracks, replaced the pads with budget street pads and added steel braided lines. Filled the whole thing up with ATE Super Blue. Braking performance is amazing. I am scared to use my brakes now for fear I'll be rear-ended everytime I do. I never knew a car could stop so fast and so smoothly! And this is just a stock Carrera system. After a simple rebuild I would bet your turbo brakes will knock your socks off.

[lendaddy]

Now that sounds great. I look forward to my results now! I wonder what your "weak link" was or if it was a culmination.?.

[n8marx]

I think it was a combination of worn pads and spongy lines. I couldn't find any evidence in my records that the lines had ever been replaced in 92K miles. Anyway, I am very pleased with the results. I have a high, hard pedal now and when I stomp on it she stops hard. Others here with high-zoot braking systems may not be as impressed but I sure enjoy the heck out of the results. I hope you enjoy the same success.

[don911]

I agree with the above that stopping power shouldn't be a problem with stock brakes. For street use, stock brakes are more than adequate. If the problem is stopping, I'd guess the system is suspect.
Heat is the only reason I am upgrading to 930's, not stopping power.

[AES]

You might profit from reading this

[aseem]

Originally posted by ChrisBennet
Asseem,
That's a good deal. I wasn't aware of an aftermarket floating rotor. I bought my last set for around $250. Discount parts places have them for over $300 and the local dealer probably wants over $400. I had VCI supplied Coleman before this set and I don't think they wore that great.
-Chris

They are OE rotors from Berlyn Services in the UK
930.351.047.00 TURBO FL DISC 80 £64.68

If you search here on Pelican , partno: H-352-045-01, you will find they are only $148, and you don't have to pay atlantic shipping. Dont know if these ar OE or after marked items

lendaddy: good luck on your upgrade, i hope you will be satisfied with your "new" brakes

[Jack Olsen]

Unfortunately, that's the price for the rear rotor, which isn't exclusive to the 78-79 models. The fronts are the tough (and expensive) part. I don't think Pelican's site even lists them.

[don911]

Yep, the fronts are the problem for narrow cars. Pelican can't get the early floating front rotors. I paid 575 for the front floaters. With hats, the pair of front rotors alone will be $1000.

[aseem]

Yes Jack, you're right. I misread the pricelist.
But still, the Berlyn price is nice isn't it, and it is genuine Porsche parts for 930 front 78-80 brakes. Are the prices much higher in the US?

If they are, Don, you should check out Berlyn, even thou you have to have them shiped across the pond.
They are nice people, but their web isn't exactly high tech

[Bill Verburg]

From the prices I am seeing the Big Red kit is looking down right reasonable @ $1795 for the front(from Pelican) which includes the 322x32mm floating Brembo crossdrilled rotors, the only downside is the extra weight of the 322s and the cost. The sweet spot is still the 993 caliper and the 993 304x32 front rotor, 2 piece floating for track, 1 piece for street.

I wouldn't bother w/ the rear kit. A better option is to use 964T rear calipers and stock 930 309x28mm rotors. The calipers are easily modified to fit on SC/Carrera trailing arms w/ 3" mounts.

Don't forget that a 930 m/c is mandatory w/ this setup.