72 Cutlass Brake Upgrade Options

[cdrod]

If you want a kit that works and includes readily available replacement parts, then give Tobin a call at Kore3 and buy his "325mm Big Brake" kit for A-body cars. This will reuse your stock drum hubs but they may need to be turned down to fit the C5 rotors. If you're on a budget, you can source most of these parts yourself from any auto parts supplier as all but the caliper brackets are over-the-counter factory parts. Keep in mind that this kit steps you up to 12.79" dia. rotors which will not fit factory rims (even 15" stock repop versions). You will need 17" at the minimum but most likely will need an 18" rim to fit over these larger rotors. You can download full size, fitment templates from the Kore3 website to check the caliper clearance inside the rim.



You can up your game even further with a spindle swap that raises the upper balljoint to improve the camber geometry. The factory A-body cars actually gain positive camber in a turn which is the opposite of what is needed for good handling; raising the upper ball joint causes the suspension to gain negative camber in a turn. This will require new upper control arms as well. As an alternative to the expensive tall spindles, you can use your stock spindles and steering arms but use tall upper ball joints to raise the upper pivot point. You can source the ball joints from Howe Racing and Pro Forged now make a tall ball joint as well. The Howes parts are rebuildable with replacement ball studs and you can get taller stud lengths up to +.9"; the Pro Forged ball joints are not rebuildable and come in a fixed +.5" & +.9" lengths. SPC makes a very nice adjustable upper control arm that works with the stock spindle and tall ball joint combo but will require minor modifications to frame supports to clear the control arms.

I did not buy the kit from Tobin for my car, as I chose to source the parts individually form Amazon, Rock Auto, and eBay. I did buy the stainless brake lines and aluminum hubs from Tobin. I used my stock spindles, SPC upper arms (#94320), Howe +.9" ball joints, Z06 red calipers and abutments (AC Delco#172-2263 & 2264), 12.79" C5 rotors (Centric#125.62059/060), I bought the caliper brackets used on eBay, and the hubs and hoses from Kore3. I measured the camber curve with this set-up on my '72 Olds 442 convertible (A-body GM) and found that the suspension gained approximately 0.8 degrees of negative camber for every 1in. of suspension travel. the camber curve was not linear as the negative camber gain increased with more suspension travel. Starting with 0 degrees of static camber at ride height, my camber was a full -4 degrees at full bump (compression) this was approximately 4in. of suspension travel.

I hope this info is helpful to you.

Rodney