What discs should i use with 944T front calipers?

Kroggers · Kroggers's Garage

I have a set of modified 944 Turbo front calipers that i am going to fit on my SC, but I am not sure about what discs I should be using? I would prefer floating rotors, as the car will be used mainly for track driving.

MotoSook · 04-17-2007, 06:28 AM

Who modified them? If they are spaced them out like the VCI kit does, then the 1986 944T/951 rotors work, but you'll need the VCI spindle spacer to push the hub out along with the rotor so you are not rubbing on the A-arm. Even with the spacer, the rotor still rubs on the A-arms when you turn. It's a terrible compromise IMO. You have to grind down the A-arm to make room...or your rotor will do the grinding for you.

Kroggers · Kroggers's Garage

Not sure who modified them, but it was done correctly - one hole was plugged and a new hole drilled to fit the SC. It was supplied with spacer washers to push the caliper out slightly if required. Is that what you are referring to when you say spaced out?

911pcars · 04-17-2007, 01:11 PM

Not sure of the particulars, but besides the 944T rotor (298x28mm), some use the 993 rotor fitted over the bearing hub instead of bolted behind it. The hub OD is machined slightly smaller for the rotor to install. Not sure of the resultant offset with the centerline of the caliper and there are wheel clearance issues with a 911 7x16, but it's in the archives somewhere.

Here's one:
My 993 big brake upgrade on the SC

Let us know what direction you go.

Sherwood

9elf · 03:56 PM

Floating 930 rotors and hats. 304mm X 32mm

Edited to '304' X 32.

Bill Verburg · Bill Verburg's Garage

If you still have the stock mounting ears on the calipers then the only rotor you can use is the Carrera 24mm. That is NOT a good idea at all.

The correct way is to use either the 944T rotors that Souk mentioned or best of all the '78-80 930 rotor that 9elf used(304x32)

To use either of the correct rotors the stock mounting ears are machined off and radial mount holes are machined in. An axial to radial adapter is then yused to bolt to the strut

Kroggers · Kroggers's Garage

Quote:

Originally posted by Bill Verburg
If you still have the stock mounting ears on the calipers then the only rotor you can use is the Carrera 24mm. That is NOT a good idea at all.

The correct way is to use either the 944T rotors that Souk mentioned or best of all the '78-80 930 rotor that 9elf used(304x32)

To use either of the correct rotors the stock mounting ears are machined off and radial mount holes are machined in. An axial to radial adapter is then yused to bolt to the strut

Thank you Bill. I do have the stock mounting ears, and they were used on a track car with a 3.6 here in Sweden for some time which had no problems. He did supply me with the discs he had used as well, but they are a bit worn and I wanted to put on new discs - that is why I was asking what disc would be best.
Could you please expand on your statement on why it is NOT a good idea, please?

911pcars · 04-17-2007, 11:09 PM

"Thank you Bill. I do have the stock mounting ears, and they were used on a track car with a 3.6 here in Sweden for some time which had no problems. He did supply me with the discs he had used as well, but they are a bit worn and I wanted to put on new discs - that is why I was asking what disc would be best."

New ones would be best.

If these brakes worked well enough in your friend's track car, why are you thinking of using a different type rotor? What are the dimensions of the worn rotor?

MHO,
Sherwood

Kroggers · Kroggers's Garage

Quote:

Originally posted by 911pcars
New ones would be best.

If these brakes worked well enough in your friend's track car, why are you thinking of using a different type rotor? What are the dimensions of the worn rotor?

MHO,
Sherwood

I do want to use the same size, but I was thinking that floating would be better and easier for maintenance and replacement in the future - is that wrong?
The discs that he gave me with the calipers are 280x24. If I am not wrong, the SC discs are 280x20. So, can I assume the 280x24 the 2.3 carrera disc?
If I was to go for new discs, what would be the best ones to get for a car that is predominantly used on the track?

Bill Verburg · Bill Verburg's Garage

Simply that the 24mm Carrera rotor is too thin. The 944t rotor is 28mm. The thiner rotor implies that the pistons can be hyperextended as the pads wear. This leads to problems. least of which is "cocked" pistons.

here is a 944t and a Carrera rotor

The only ones available floating are 304s
Oems are the better choice
here an oem 304x32 vs an aftermarket 304x32

If you use Carrera rotors you might as well use Carrera calipers.

Kroggers · Kroggers's Garage

Thank you for all the good information Bill. As I got the calipers at a good price, I will try them to start with and see how things go.