Brake upgrade pros and cons

[JeremyD]

OK - Following the Ultimate Brake Upgrade Page - and the valuable Bill Verburg - seems like there are many options out there - Upgrade Thread

But also seems like there are pluses and minuses to each one - Just want to make sure I am not missing anything here -

I have a set of 944t calipers - also have a set of 993 calipers on the way

Using the 944t calipers - 1 - have to machine them - VCI can do this - using the 951 rotor is a bolt on - (cheap) downsides are that you either have to space the hub out 4mm or grind down the a-arm ball joint. Also - the rear is a compromise - the pads hang over and to make a 930 rear rotor fit - custom hats.
944t on a 911 thread

Using 933 calipers with a 930 rotor - have to use the early 930 rotor - with no offset.
Pricey! Custom hats - pricey too. I have read where some folks use the stock Carrera pots and some upgrade to the c2 964 pots (aren't these essentially the same?)

3rd option is the Instant G
custom Hubs - 996 brakes and c2 rotors that go over the hubs...

Instant G This looks like a pretty good solution - still $3K in brakes before you are done.

Anything else I am missing? Anyway to do fronts and rears for under $2K? My Car is a 87 Carrera Cabriolet

[JP911]

Will your Fuchs still fit over the 993 or 996 brakes?

[89911]

Biggest question is: Do you really need them? I upgraded mine because of extensive pad wear and fade during track runs, sometime 40 minutes continous on open track days. The 930 upgrade was expensive, the rotors are more expensive, and the pads cost more. Other then those factors, its great . The car stops well and there is little or no fade. My brother went with Big Reds on his car. The intial outlay is more, but I bet over time his will be cheaper. I went with the 930's because I would have to part with my beloved Fuchs, which you will if you go with any other calipers. Like I've said before, Ain't nothin money can't fix!

[JeremyD]

Well - three track sessions - three issues with brakes. First one spongy pedal in the middle of a session. (full bleed and flush) 2nd - tore through a set of pads down to the metal (yes I was a dumba$$ and used stock Mintex - was told by the track inspection guy - you'll be fine...) when I went to replace the scored rotors - part of the caliper boots tore off in my hand - can we say - they got hot!- 3rd time with AJ-USA coolers - and better pads - spongy brake pedal again.

Will my 8" 951 offset fuchs fit over 993 brakes?

[Bill Verburg]

I agree w/ Mike. the Big Reds are more upfront but over the long haul are a far better choice.

Given that you don't want to buy new wheels the 993 calipers on true 930 rotors is a good compromise.

For the front all you need to use the 993 calipers are some caliper adapters, flex lines, 930 rotors and hats. The rotors can be sourced at Elephant, Rennsport or R&D, the hats at Rennsport, VCI, Imagine, the lines ditto, the caliper adapters ditto.

For the rear a better choice is the 993 rear calipers on 930 rotors but the 964 will work ok(it is going to be front biased). The throat and ears of either will need to be modified but that can be a diy. The 965 calipers on 930 rotors is best because only the mounting ears need mods and the bias is best.

Dr. Ts set up is an interesting idea, but it does change the geometry of the front end, meaning normal +23.3mm wheels won't fit too well and you need 17" wheels.

[IROC]

Well, with only three track sessions under your belt, I would examine your braking technique for starters. Most beginners on the track brake incorrectly. You need to brake as hard as possible for the shortest amount of time as possible. The same amount of heat energy is generated (you're slowing the same mass from the same velocity), but the brakes will have longer to cool off as you won't be using them as much. I had this same problem when I started doing DEs 10 years ago.

Porsche puts some of the best brakes known to man on their cars from the factory. Unless you have modified your car to be much quicker than the factory intended, your brakes should be adequate as long as your fluid is in good shape and there aren't any other anomalies.

Mike

[bigrubberjeep]

Another way to reduce brake wear is........Reduce weight of car.

The less weight the brakes have to slow, the longer they will last and the less heat they will produce.

Not to mention all the other benefits of weight reduction.

[xlr8]

How about some HRE 17" 311's for big brakes and the Fuchs look?

[89911]

Last time I looked, weren't they around $7-800/wheel.

[JeremyD]

Originally posted by bigrubberjeep
Another way to reduce brake wear is........Reduce weight of car.

The less weight the brakes have to slow, the longer they will last and the less heat they will produce.

Not to mention all the other benefits of weight reduction.

Remember I have a fat a$$ cabriolet - luckily I have a manual top or I'd only get 1/3rd a session. I know about the brakes too - but when you have little confidence in your brakes, especially a track like sebring, you tend to get on them a little earlier...

I have three DE's in the car but I have alot more track experience including instructing at a local test track (Primus)

[Eagledriver]

Are you using a high temp fluid like ATE blue?

[dean]

I paid about $2700 for my 930 setup. I paid the going price for everything. And I'd do it again in a heartbeat. I don't think you can do it for much less.

[JeremyD]

Originally posted by Eagledriver
Are you using a high temp fluid like ATE blue?

Yes - ATE Super Blue - at the recommendation of a few track junkies - just flushed out the blue for Motul 600 -

[911-32]

Maybe there is some middle ground. Seems to me that a lot of 3.2 guys want a "little" more brakes but don't want to pay for a "lot" more brakes. What about the VCI 944T/964 kit?

Seems like a very cost effective upgrade if you just do the fronts and leave the 3.2 rears as is. Any reasons why not? The 3.2 rears are only slightly smaller than the 964 C2 2 pot rears so bias is very similar once once the proportioning valve is removed. You get a bigger 28mm thick front rotor, bigger front pads, better clamping from a big stiff caliper and 944T/964 front calipers are cheap as chips to buy. You should be able to get this done for about USD1,000.

Whats not to like about that? Sure it isn't the ultimate but IMHO it is just about right for a lightly modified 3.2 or SC used for DEs.

Richard

[RickM]

If I can get a full set of '97 993 calipers for free what am I looking at $$$ for using them on my '85 Carrera? Just rotors and hats? Do I have to go to 17" wheels with this conversion?

[Rick Lee]

My stock 993 calipers will be for sale soon. I have Big Reds in the mail.

[89911]

Originally posted by 911-32
Maybe there is some middle ground. Seems to me that a lot of 3.2 guys want a "little" more brakes but don't want to pay for a "lot" more brakes. What about the VCI 944T/964 kit?

Seems like a very cost effective upgrade if you just do the fronts and leave the 3.2 rears as is. Any reasons why not? The 3.2 rears are only slightly smaller than the 964 C2 2 pot rears so bias is very similar once once the proportioning valve is removed. You get a bigger 28mm thick front rotor, bigger front pads, better clamping from a big stiff caliper and 944T/964 front calipers are cheap as chips to buy. You should be able to get this done for about USD1,000.

Whats not to like about that? Sure it isn't the ultimate but IMHO it is just about right for a lightly modified 3.2 or SC used for DEs.

Richard

The 3.2 rears are small, very small. They are somewhat in balance with the Fronts in size, but still smaller. Making the front bigger will now give you an essentially front braking car. The only way to balance this would be to choke the fronts and give more bias to the back. What good would that do?

[Glasgow 911SC]

Originally posted by 89911
The 3.2 rears are small, very small. They are somewhat in balance with the Fronts in size, but still smaller. Making the front bigger will now give you an essentially front braking car. The only way to balance this would be to choke the fronts and give more bias to the back. What good would that do?

But surely on a 3.2, it would be too strong at the rear with no P/V and the standard front calipers. Therefore you would have to increase the front piston area to get a good balance when 3.2 rears are used with no p/v.

I think there's a few guys on here that have used the 964 fronts on 3.2 rotors to good effect. GeorgeK, Ed (Dutchie)??

[JeremyD]

Originally posted by xlr8
How about some HRE 17" 311's for big brakes and the Fuchs look?

Very nice - although the divorce would cost me more than the 700-800 a wheel. Let's see - 3,000 in brakes another 3200 in wheels - my last divorce cost me around $68K - NAH - no contest...

[911-32]

Originally posted by 89911
The 3.2 rears are small, very small. They are somewhat in balance with the Fronts in size, but still smaller. Making the front bigger will now give you an essentially front braking car. The only way to balance this would be to choke the fronts and give more bias to the back. What good would that do?

Not true. The discs are the same thickness as the 964 rears - 24mm - and only a little smaller in diameter. The 2 pot calipers on a 964 C2 are virtually the same size as the 3.2 (pistons are slightly bigger on the 964 caliper). The upgrade I describe would give you virtually identical brakes to a 964 C2 - in size and bias. If this works on the heavier 964 then I reckon it is just the ticket for a moderately lightened 3.2.

I have been discussing this with one of the foremost Porsche race shops in the UK and they think the bias will be close enough to work just fine. At the very worst you add in an adjustable bias valve. My 964 calipers are getting the VCI mods right now - so I guess I am putting my money where my mouth is.

The reason for a proportioning valve in the std 3.2 is because the rear brakes are too strong, therefore it certainly makes sense to beef up the fronts.

Richard