Lorax

With the proper adapters you should be able to use brakes from 928s4, same ones that come on 944turboS. Not too much difference in pad surface area, but a much larger rotor and bigger pistons.

They fit under the 16" wheels that come on the 951S, I would venture to guess the would fit under your wheels as well.

Dave in Chicago

The stock brakes use the same pad size front and rear. The difference in the calipers themselves are the piston sizes (I'd have to look up the PET to tell again what they are). Using the same pads allows for a bit of rotation flexibility that I miss.

The M030 option (sport option) added different spindles and hubs (presumably to allow for the clearance of the radially-mounted calipers versus the axially mounted stock units). They're supposed to be beefier, but I haven't seen them side by side, so maybe it was just Porsche's way of providing fit. The Racers Edge adapters solve the mounting and alignment problem, allowing quick conversion from stock to M030 caliper and rotor, without any change to spindle or hub.

More importantly, the M030 calipers and rotors (yes, they are the same as the 944 Turbo S, 944 S2 with M030, etc. - caliper casing changes over time, piston sizes and order do not) add a fair amount of unsprung weight at the front wheels. In fact, they add almost as much as converting to Big Reds without giving nearly the same "hand of God" level of braking.

I only run the M030 units because my 968 is an absolute PIG in PCA E-stock at 3186 lbs. I agree with those above that recommend sticking with the stock brakes. They're quite good, allow quick pad changes, seem to be in good supply and help keep the unsprung weight down.

If you have a set to install, be sure to clean them and replace the little spring plates at the ends of the pad openings (held in by one screw each, torx IIRC). These calipers corrode in this area (aluminum against the stainless spring plate) and eventually you cannot slide pads in / out without filing or shaving them. The right fix is to take the evil little screw out (turns with a careful tap against a cold chisel) and scrape the area beneath the plate flat. Porsche sells new plates with a screw as a kit.

You will save yourself hours of time versus trying to get pads to fit the less-than-ample slot on corroded calipers.

Good luck with this project. You are building a very intriguing car that any of us in the 924/944/968 world would love to see!

samluke

The MO30 calipers and rotors for the 944 and 968 series are the 928 S4 calipers and rotors.

308mm diameter in diameter. They are the biggest you can get inside the 16" wheels. The MO30 calipers mount radially, not axially as the standdard 944/Turbo calipers do. The MO30 splindles have the radial mount for the calipers, plus are thicker in diameter. They are the strongest spindles in the 944/968 series cars.

You can use the S4 calipers with the stock spindles by using adapters.

The big benefit of the MO30 setup is the cooling capability and pedal feel. The stock brakes suffer from overheating and thermal cracking at the track. Even the MO30 setup is not enough to prevent this, but its better. The downside is the extra unsprung mass.

944's/968's are in the 3000lb range. If your only 2000lb then the overheating is less of a risk. A light car would benefit from the lighter unsprung mass and you don't really need the big brakes. The smaller set up uses lower cost pads and rotors which is also a benefit.

There are many different piston sizes for the standard 944Turbo/S2/968 calipers, which are also used on 964's 993's etc. You would probably be best going for the largest piston sizing for lightest pedal effort.

I have a number of sets of Turbo/968 calipers with various piston sizing, if you need any.

mattipuh

I would be interested in larger front calipers to 968, if you have any available.

br.,
Matti