72 Cutlass Brake Upgrade Options

[72cutlassS]

I have a 72 Cutlass that was a factory drum brake car. At some point in its past was upgraded to front disk brakes. My goals for the car are a mild pro-touring inspired build for street use (might attend some random track night in america events or something). 17x9 wheels have been purchased and am thinking of brake upgrades in the future and am looking for some insight.

Front:
Seems the CPP C5 upgrade is a good value to get some larger rotors/calipers. Best I can tell the spindle should work with stock or aftermarket arms, I have BMR front uppers (not installed yet) and plan to pick up the lowers as well. Ebay browsing doesnt seem like i could do any better piecing a kit together with c5 calipers, drum brake hubs etc. and I dont want to spend money on the big kits at this time. Going with the wilwood d52 calipers for now almost brings the cost up to the kit.

Could the CPP front kit work with existing master/booster/rear brakes until i upgrade the rear as well as after rear is upgraded?

Rear:
Currently factory drum, looks like 98-02 Camaro rear backing plates/brakes work on the a-bodies but I have seen some brake kits mention differences with oldsmobile and other rear ends. What is needed to make these work on an olds rear?




Trying to plan out my build. Front will be BMR upper and lower arms with tall upper and lower ball joints. Currently on 1" lower spings I believe but will be going lower.

[olds70supreme]

I'm in a similar boat (68 Cutlass). I've been planning my upgrades for almost 2 years now, but keep getting derailed by other things.

One thing I came across in my research is feedback about the CPP spindles including bad geometry and poor tech support. A member called HWYSTR455 on the maxperformanceinc website posted his experience. That convinced me that I'll be going a different route.

[72cutlassS]

I'm in a similar boat (68 Cutlass). I've been planning my upgrades for almost 2 years now, but keep getting derailed by other things.

One thing I came across in my research is feedback about the CPP spindles including bad geometry and poor tech support. A member called HWYSTR455 on the maxperformanceinc website posted his experience. That convinced me that I'll be going a different route.

Thanks for the reply on that. I was not able to find any reported issues but also couldnt determine how or if geometry was changed with them. Guess I will stick with stock spindles and tall upper/lower ball joints.

I came across a youtube video of someone using stock drum hub with c3 rotors? and c5 calipers and brackets from cpp. doesnt look like that is a kit anymore but I could probably fab some brackets. Are the drum and disk spindles different?

[72cutlassS]

Here is a snip from a post on a chevelles forum.

[csouth]

Thanks for the reply on that. I was not able to find any reported issues but also couldnt determine how or if geometry was changed with them. Guess I will stick with stock spindles and tall upper/lower ball joints.

I came across a youtube video of someone using stock drum hub with c3 rotors? and c5 calipers and brackets from cpp. doesnt look like that is a kit anymore but I could probably fab some brackets. Are the drum and disk spindles different?

Hit up Tobin at kore3.com He can help you with C5 brackets for stock spindles. He also has rear brackets for c5 setups. He's very knowledgeable about these setups.

[tillmatic]

Using the G Comp spindles from speedway motors on my 72 cutlass.

2 inch drop performance spindles for use on 1967-69 Camaro, 1968-74 Nova and 1964-72 Chevelle
Upper ball joint location is raised to provide added negative camber gain and improved handling
1-piece forged construction using 4140 chromoly steel to maximize strength for both street and track use
Utilizes OEM bolt-on power steering arms as well as OEM replacement ball joints for a simple bolt-on installation
Compatible with OEM and aftermarket disc brake kits which allows countless brake options

Cant post a link but you can find them on their site.

[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

[72cutlassS]

Seems like CPP spindle may not be the way to go. Unclear on any geometry or bumpsteer changes from what I researched.

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

Rodney,

What are you running for rear brakes and master cylinder?

[Charlie_in_OC]

+ 1 @ Tobin from Kore3, a wealth of knowledge and excellent product support. Since you already have 17" rims I'd lean towards 98-02 4th gen F body front and rear, I ran that set up on my 64 Skylark wagon and never felt I "needed" better brakes in spirited street driving.

As for BOP non c clip axles, I needed to lightly file one hole on each F body backing plate to fit my 64 Buick 10 bolt, other than that every thing bolted together fine.

[cdrod]

72CutlassS:
My rear brake set-up is from a 2001 Blazer 2WD. I chose this set-up over the more typical LS swap mostly because the Blazer backing plate 1included a built-in ear for the parking brake pull and the slightly larger caliper diameter. This required a 1/4" spacer behind the backing plate to center the rotor in the caliper. I was able to shorten a pair of stock Cutlass parking brake cables to work with the Blazer backing plate. I did a trial fit of LS parts but the caliper was not centering well and it was obvious the parking brake set-up was going to take some work.

Here are some stats to compare the 2 swaps:

Blazer set-up:
Rotor: 11.61" dia. 0.79" thick, weight 14 lbs.
Caliper: 48mm dia. single floating

LS set-up:
Rotor 12.01" dia. 1.02" thick, weight 14.5 lbs.
Caliper: 45mm dia. single floating

[jetmech442]

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

This has a lot of good info Rodney.

Like you said, not sure if the 17'' rims will fit the 325mm rotors. The original D52's are a great caliper though, very stiff and way more piston area than the 6 piston Aero6, plus will fit under 15'' rims. Going with either a taller spindle(AFX), or upper/lower tall ball joints and the upper control arm to dial in settings will get you into good brakes AND great handling.

For reference, my 69 442 started out with the CPP stock disc brake kit front/rear. This got me into disc brakes the easiest, but the spindles they use don't have the best geometry and the rear calipers(d154) with integrated parking brakes are nearly impossible to adjust properly(I tried for 6 years).

I quickly went to wilwood D52's for better looks and less weight. Eventually I switched the rear D154's out with Wilwood D154's WITHOUT the parking brake and all my soft pedal issues were instantly solved.

Currently, I have ditched the CPP drop spindle, replaced with a stock spindle, installed Howe's upper and lower BJ's like Rodney said above. And the SPC upper and lower control arms. I'm running Tobin's (from Kore3) C6 Z06 adapters and the Aero6 caliper and 14'' rotor. I ran the SPC uppers for over 8 years, and only recently went with the SPC lowers since I found issues with my stockers. The SPC lowers allow me to get back my 2'' drop that I lost when going back to stock spindles.

[72cutlassS]

Just to give an update on where I stand. I did reach out to Kore3 to discuss options. Although not shown on the site, they do offer a rear kit for bolt in axle applications. I did not get any specifics on pricing at this time.

After thinking things over I am going to plan to go with speedtech AFX spindles. Will improve geometry, give 1 inch lower height, better hub and allow use of c5/6 calipers. Kind of a two birds one stone situation. Will still try and get the bmr lower control arms as well to match the uppers.

I will source some used calipers from ebay

Hopefully I will be able to purchase just the rear adapter pieces, rotors, pads from Kore3. Will have to confirm.

If I can manage all that and probably swap rear springs out for another inch or two lower, with the new wheels and tires the car should be transformed and i can start looking at other upgrades.

[jetmech442]

AFX spindles are like killing 9 birds with one very expensive stone. Eventually I would like to be able to get some for mine. Good luck man.

[72cutlassS]

AFX spindles are like killing 9 birds with one very expensive stone. Eventually I would like to be able to get some for mine. Good luck man.

Thats the struggle, as i wanted to just collect parts over time without spending a decent chunk of money. Every other scenario seemed like i was coming up with a temporary decision and would have to do over eventually and spend more in the long run. Replacing body bushings raised the body enough that with the new wheel/tire combo I will want to go lower. The drop with AFX spindles is how I am helping to not justify spending the money on converting to coilover in the front.

[72cutlassS]

Back into looking into this again, I have tried to get confirmation from Speedtech twice but have not gotten a reply. I am not sure if their spindle comes with any steering arms at the $1300 cost. I know they mention 2 options for ackermann/bumpsteer correction arms that can/have to be purchased separately. Both of these options will not fit 17" wheels, which is what I recently got.

Therefore I am back to considering the CPP option and global west bumpsteer correction arms and tall lower bj or KORE3 brackets and drum hub.

The 1" drop with ATS AFX spindle would have been very useful.

[72cutlassS]

So I kinda have a lessons learned situation. With c5 brakes being 325mm I didnt think anything of 17 inch wheels fitting as I come from Volvo s60R world were 17" wheels are standard on the car which comes with 330mm brembos all the way around. Downloaded the template for 325mm fitment and guess what, they will not fit in my wheels.

I will not be able to run C5/6 brakes or AFX spindles with the yearone SSII wheels. So back to the drawing board.