951 brakes on a 911???

markmaunz · 08-16-2005, 07:59 PM

Hi folks, Ive noticed that a few people have used 944 turbo brakes on some 911's. How does this work??? Is it both front and rear that work? Thanks, Mark

Bill Verburg · Bill Verburg's Garage

the 951/944t/964 brakes are a very nice setup for a 911 when done right.

Right means using them on either 944t or 930 rotors, or equivalent aftermarket rotors.

look here for one way to do it

look here for another way to do it

look here for an outline of all the available ways to do it

That said the 951/944t/964 brakes are not the best bang for the buck.

the sweet spot or best bang setup will be 993 calipers on 930 rotors

patkeefe · 01:08 PM

I have a short, immediate window of opportunity to pick up the brakes from a 951 which, unfortuneately, burned. I am going over to look at it in about five minutes.

Is it worth it to pluck the rotors and calipers from the hulk? The price is right!

Forgot to mention they will end up on my 78 SC...I'll need more brakes when I put the BAE in.

Thanks!
Pat

Bill Verburg · Bill Verburg's Garage

They are a lot of work to adapt to a 911, probably not worth it.

patkeefe · 05-13-2006, 03:48 PM

Bill:
After looking them over, I agree with you.
Thanks!
Pat

Clay Perrine · 05-13-2006, 04:53 PM

To adapt 951 brakes to a 911 (Or in my case a 914) you have to do some major modifications. On the front, the calipers have to have the holes offset drilled to accomodate the different bolt spacing. The 951 calipers use a 3 3/4" bolt spacing, and the 911 uses a 3 1/2". Plus the bolt center is slightly off so they have to be drilled at a 45 degree angle.

On the rear, the bolt spacing is 3" (911 or 914). So the only proper way to do this is to cut the mounting tab off the trailing arm and weld a new one on that accomodates the proper offset and caliper depth.

When you do this, you have to use Carrera rotors front and rear to get the proper offset and spacing.

You do get very good brakes out of the deal, but you can get better brakes by getting Boxster monoblocks and buying adapter plates. Those are a true bolt on.

patkeefe · 05-13-2006, 05:11 PM

Thanks, Clay:
I have a set of S4 brakes in the garage, destined for the fronts of the SC, which have the adapter blocks, which are incidentally the same brakes as on my 968. I was looking to find something for the rears, to even up the bias, hence considering the 951 rear brakes. This particular 951 has the smaller calipers in the front, although the rears look like they would work out with some mods.

My 914 has Carrera brakes front and rear. Since I just decided to pull my badly leaking engine from the SC, rebuild it and put the turbo kit on, I figure I have about 30 days to come up with a brake upgrade solution. I will hate to find that I don't have enough braking power while going down the chute at Watkins Glen.

I'll do some more searching on brakes, and check some of Bill's recommendations.

Thanks!
Pat

Clay Perrine · 05-13-2006, 05:24 PM

If you want to do the Boxster monoblocks.. I would suggest that you contact Rich Johnson. He makes and sells the caliper mounts for the monoblocks to fit a 914. You have to have 911 front struts with the 3 1/2" bolt spacing, but the rest is a bolt on.

Rich can be contacted at a914guy@aol.com

randywebb · 05-13-2006, 06:16 PM

remember folks -- the heat dissapation will be determined almost entirely by the rotor, and the transient heat absorbtion will be determined almost entirely by the rotor...

patkeefe · 05-13-2006, 07:41 PM

Now, Randy, did you have to bring up that Fourier stuff?

Bill Verburg · Bill Verburg's Garage

Quote:

I was looking to find something for the rears, to even up the bias, hence considering the 951 rear brakes. This particular 951 has the smaller calipers in the front, although the rears look like they would work out with some mods.

The S4 front calipers are the same as the 993 front calipers(except for the reversed feed/bleeds), you want(in order of preference) 965 rear or 993 rear calipers in the back.

any 928,944,951,968 or 964 rear caliper has pistons which are too small.

Using the 964/944t/Bxster etc calipers on Carrera rotors is mostly an appearance item. The only aspect of a 911 brakes that needs improvement is thermal performance at track days. The Carrera rotors are a small step in that direction and may suffice for many. To get truly bulletproof brakes(within reason) you need 930 or better rotors.

Clay Perrine · 05-14-2006, 06:32 PM

Quote:

Originally posted by Bill Verburg

any 928,944,951,968 or 964 rear caliper has pistons which are too small.

This is true for a 911, but not for a 914. The weight bias is completely different. A 911 needs more rear brake bias than a 914 does because the 911 has more weight back there.