Help with custom disk / caliper arangement

[matt2000]

Hi,

I am posting this message as I am in dire need of help for my front rotors / caliper set up.
I bought my cat ~8 years ago ( 911 SC for 1979). It was quite heavily modified, which I did not fully realized art the time.
Long story short, we are doing a rebuild of the front end, and my mechanic noticed that the rotors have some sort of custom adapters that is cracked.
We measure the disks ( pic below) but can t figure out where they are from...
calipers look like 944T or early 964s...
Rotors are 305 ish x 30 ish.
Any suggestion as to what rotors of similar size i could fit ? the hubs are standard 1979SC. Trying to avoid having to go the 930 floating disk set up as they cost a bomb.

Thanks for your help! pics below

[Bill Verburg]

Originally Posted by matt2000

Hi,

I am posting this message as I am in dire need of help for my front rotors / caliper set up.
I bought my cat ~8 years ago ( 911 SC for 1979). It was quite heavily modified, which I did not fully realized art the time.
Long story short, we are doing a rebuild of the front end, and my mechanic noticed that the rotors have some sort of custom adapters that is cracked.
We measure the disks ( pic below) but can t figure out where they are from...
calipers look like 944T or early 964s...
Rotors are 305 ish x 30 ish.
Any suggestion as to what rotors of similar size i could fit ? the hubs are standard 1979SC. Trying to avoid having to go the 930 floating disk set up as they cost a bomb.

Thanks for your help! pics below

Hard to tell from the pics but it's likely a 944t or 964, hopefully front caliper. It's difficult to tell from the pics because the largest different between the various calipers used on the 944t & 964 was the piston size, the fronts were also wider but that's even harder to differentiate.

hopefully he pistons are 40/36, You need to pull the outer seals to measure beneath them.

The caliper has been modified from stock axial mount w/ ears to a radial mount w/ a caliper adapter, it looks like the job was nicely done.

The rotor is likely an aftermarket, Coleman or similar 304x32 w/ a flat, non floating hat to adapt it to the 911 hub. The rotor annuli were/are available in plain, grooved and drilled. THey are often called 930 or turbo rotors because their size is the same as was used on the '78-89 930.

Hopefully the rear is a slightly modified 964 caliper on a stock 930 drilled rotor and also hopefully a 930 23.8mm m/c was installed.

[Dan J]

Bill's right ( as usual) Hey Bill!
That rotor and hat is available from Doug Arnao @ VCI
https://www.vehiclecraft.com/

[Bill Verburg]

Originally Posted by Dan J

Bill's right ( as usual) Hey Bill!
...

Back at you

Hope you all are doing well down there

[matt2000]

Bill, Dan,

Thanks a lot guys! amazing knowledge!
I have reached out to Doug at VCI, hopefully he still has the disks and flat hats.

and yes the rears are 930s calipers.

any other suggestions to source disk and hats? I checked Coleman but they didn't seem to have the hats on their website.

Best regards,

Matt

[Bill Verburg]

Originally Posted by matt2000

Bill, Dan,

Thanks a lot guys! amazing knowledge!
I have reached out to Doug at VCI, hopefully he still has the disks and flat hats.

and yes the rears are 930s calipers.

any other suggestions to source disk and hats? I checked Coleman but they didn't seem to have the hats on their website.

Best regards,

Matt

As I recall, both Coleman & Wilwood custom make the hats, you have to provide them w/ the specs or one to copy, the rotor annulus is a common size 32x304mm

Seems like the thing to do is just get them from VCI

[gremlin]

Is it Coleman or Cullman? I can't recall, but my '71 T has 964 front and rear calipers on it. On the front we had a custom made rotor that is 964 thickness but the correct diameter, so that we didn't have to slip shims between the pads and the pistons. This does necessitate milling the pads a little to clear the custom hat, so check the backing plates for that mod.

Cantrell Motorsports helped with this setup you could talk to them.

[Bill Verburg]

Originally Posted by gremlin

Is it Coleman or Cullman? I can't recall, but my '71 T has 964 front and rear calipers on it. On the front we had a custom made rotor that is 964 thickness but the correct diameter, so that we didn't have to slip shims between the pads and the pistons. This does necessitate milling the pads a little to clear the custom hat, so check the backing plates for that mod.

Cantrell Motorsports helped with this setup you could talk to them.

Not really relevant to this discussion. The caliper here has been modified to accept a caliper adapter which places the caliper in a specific position relative to the rotor which in this case needs to be 32x304 on a flat hat, anything else won't fit together right

[gremlin]

Sorry I did read that, and then got hung up on the discs instead. In my case the 964 brakes we just elongated the holes and they bolted in to the factory mounting points so I can't help you.

I did find my invoice and they were Coleman on my car.

[matt2000]

Originally Posted by Bill Verburg

As I recall, both Coleman & Wilwood custom make the hats, you have to provide them w/ the specs or one to copy, the rotor annulus is a common size 32x304mm

Seems like the thing to do is just get them from VCI

Yep, Doug replied. a couple weeks of wait and they should be on the way.

thank again for your help guys! amazing how quickly you solved my problem