Rear Disk idea 1969 Mach1

[Mo's1969]

OK here is a weird one. My project was started by someone before me so some things where done I would not of.

The car was a 9 second drag car. Framed and had narrow rear end with tubs. The owner before me had a full length rear end installed and left the tubs.

I ordered my Centerline 10" wide 15" rims with 6.5" back space so I could stuff tires inside wheel wells.

I just installed a disk brake kit that uses GM Calipers from a 1980 Eldorado. When I went to reinstall the rims they would not fit over calipers. I called the disk brake kit seller who told me to grind down the calipers. I ground them down until they no longer hit but I am now worried.

How much clearance do I need when brakes heat up on road?

Are there other calipers that would fit better?

I don't want to change wheels tires as they are brand new and fit the look I want.

I appreciate any help

[Mo's1969]

anyone?

[Apogee]

Did you consider running a wheel spacer for caliper clearance? As for clearance between the caliper and wheel, an 1/8" should be sufficient...although I've never been a fan of grinding on calipers since it only weakens the caliper and increases deflection during operation which negatively impacts pedal feel and modulation. That said, it tends to be more of an issue with aluminum calipers than cast iron due to their different modulii of elasticity.

The 1978-1986 Caddy calipers have the same form factor as a standard D154 small metric GM caliper, however there really aren't any great aftermarket options that I'm aware of that will maintain the parking brake functionality. To be fair though, even the Caddy calipers aren't that great at maintaining their own parking brake functionality, but that's another issue all together.

Tobin
KORE3

Tobin
KORE3

[Mo's1969]

I ended up with spacer. It took the 1/2" and grinding to clear the reinforcement area of the rim.

Thanks for the help. I think when if I ear these tires out I will switch to larger rims and proper disk brake set up all around