Low Budget: convert 4-wheel drums to 4-wheel discs for $800!

[Derek69SS]

Jim asked me yesterday on Chat about my brakes, so I figured if I'm compiling info, I might as well share with anyone interested

All prices and part-#s listed are current as of today, 01-25-06

Modifying stock DRUM spindles to use stock 11” DISC BRAKES on ’67-69 F-body (Camaro, Firebird), ’68-74 X-body (Nova, Omega, Ventura, Appollo), and ’64-72 A-body (Malibu/Chevelle, Monte Carlo, El Camino, Sprint, Skylark/GS, Cutlass/442, LeMans/GTO)

Spindles: $0 (assuming your car has drum brakes on it.) These can be “converted” to disc brake spindles with an angle grinder in about 20 minutes each.

Caliper Brackets .................................................. ............$79.95 pr +shipping
Bolts .................................................. ..........................$1.95ea (x2) = $2.90 pr
Backing Plates (optional - you don't really need these)............................$39.95 pr

*note: I used Ground-Up’s prices because their website is easiest to navigate. Other sources may be cheaper, or have cheaper shipping*

The procedure for making disc spindles from drum spindles is simple. Bolt the caliper bracket tight. (but loose enough so you can rotate the bracket) to the lower bolt boss on the spindle. Then start grinding on the upper bolt boss on the spindle until the bracket can sit flat on both the upper, and lower surfaces. You will need to remove about 5/16-3/8” from the upper boss (estimated - I never actually measured).

The rest of the parts can be bought at any parts-store… NAPA part numbers and prices: (retail price)

Calipers w/ hardware #542-2016………17.75 ea + $9.00 core = $53.50 pr
- they include the caliper bolts and copper washers for the brake line.
Premium Brake pad set #AE728A…………….…….........…….……….. $30.47 pr
Economy “Loaded” Calipers…..…$28.70 ea + $9.00 core = $75.40 pr
Premium Rotors #85532 …………………………..…….$77.31 ea (x2) = $154.62 pr
Economy Rotors #4885532………….....…. $46.88 ea (x2) =$93.76 pr
Inner bearings #BR6…………………………. $7.31 ea (x2) = $14.62 pr
Outer bearing #BR2…………………………… $7.45 ea (x2) = $14.90 pr
Seal #17187………………………….…..……… $2.08 ea (x2) = $4.16 pr
69 camaro brake hose #36672……....……$18.92 ea (x2) = $37.84 pr
– on chevelles, drum cars had a different bracket, and the camaro hose fits better.
Banjo bolt #82701…………………….……… $3.46 ea (x2) = $6.92 pr

Total: (Economy)…………………………………….......………….$330.45
Total: (Premium)................…………………………………………………………..$ 439.83

REAR Disc Brakes for GM 10-bolt &12-bolt

Brackets from Steeltech Solutions: .....................$89/pr +$10 shipping = $99

Again, the rest can be bought at any Parts Store (Prices & Part #s are from NAPA):

Rotors – Rear 11” rotors for ’80 Trans-Am #85774... $41.16 ea (x2) = $82.32 pr
Loaded Calipers (w/ E-brake)…...………. $127.46 ea + $66 core = $386.92 pr
– 85 Caddy Seville rear disc calipers.
Loaded Calipers (w/o E-brake)……….....$34.75 ea + $22 core = $113.50 pr
– 85 Camaro FRONT calipers. (I think I bought mine for ½ that price from Auto Zone)
Hoses – for ‘85 Camaro front……………………….$13.79 (x2) = $27.58 pr

Sub-Total w/o E-brake……………………...……….………………. $322.40
Sub-Total w/ E-brake: $595.82 -cheaper just to buy the kit from Steeltech: $499.00

Then to make everything work properly, I used:

’68 Corvette manual Master Cylinder (NAPA #101371)….…............$20.69
Power Brake booster – ’69 Chevelle (NAPA #5471105) ………….....$81.87
Wilwood adjustable proportioning valve (Summit Racing)……….......$50.00

Sub-Total:..................…………………………………………………$152.56
My Sub-Total because I used a $25 used booster from a junk-yard:..…… $95.69

TOTAL (With all NEW parts, but done as cheap as possible)….…..$805.41
(upgraded parts prices listed so you can calculate your costs accordingly)

[Silver69Camaro]

I ran those numbers a while back too. You really can do it for cheap (w/o E-brake, that is).

But here's where I got hung up. Those Caddy calipers are aweful, bad enough to where I'd rather use 11" drums. If you can use a different caliper (w/o E Brake like you mentioned) you'd be much better off. If you want to keep the e-Brake, go aftermarket or modify the Ford SVO rear setup to work with your housing ends and axle offset.

[Derek69SS]

Originally Posted by Silver69Camaro

Those Caddy calipers are aweful, bad enough to where I'd rather use 11" drums. If you can use a different caliper (w/o E Brake like you mentioned) you'd be much better off. If you want to keep the e-Brake, go aftermarket or modify the Ford SVO rear setup to work with your housing ends and axle offset.

A lot of guys use a motorcycle brake on the pinion like this one from www.einstyn.com/


I'm a flatlander with an automatic. I haven't used a parking brake in years (except to do 180s on ice in my bonneville ) so I didn't worry about it.

[SoCal69]

I bolted a set of 2002 LS1 Camaro rears on mine. Fit like a glove and the e-brake is easy to hook up. Tried SSBC rears but I couldn't live with the e-brake and couldn't get them to tell me what the rotors were.

[Derek69SS]

Originally Posted by SoCal69

I bolted a set of 2002 LS1 Camaro rears on mine. Fit like a glove and the e-brake is easy to hook up. Tried SSBC rears but I couldn't live with the e-brake and couldn't get them to tell me what the rotors were.

What size rotors do the LT1 and LS1 brakes have? Will they fit in a 15" wheel?

I wouldn't want to be limited to 17" on the rear in-case I decide to bolt on some cheap slicks and go drag-racing.

[MaxHarvard]

I used a set of calipers from the front of an 80 camaro... installed perfectly and work really nicely... just no e-brake.

[dougs68ss]

check out performanceonline.com they have great kits for front and rear 13'' with pb caliper ,no waiting and reasonable.

[SoCal69]

Originally Posted by Derek69SS

What size rotors do the LT1 and LS1 brakes have? Will they fit in a 15" wheel?

I wouldn't want to be limited to 17" on the rear in-case I decide to bolt on some cheap slicks and go drag-racing.

Rotors are 12" on LS1. I'm not sure what dia. wheel will clear it.

[62fairlane]

I knwo it isn't an f-body but I did mine for about $400. I just pressed the old drum brake hubs off the drums on the front so I could stick late model mustang rotors on them. then made a bracket to bolt in place of the drum backing plate to hold the caliper, in back just used the stock stuff for the mustang also and am just gonna weld it to the housing...unless I get fancy and build a bracket to bolt it on with. I got $100 in the rears and $150 on the fronts and then another $150 in the stock hydraboost setup (with master and prop valve)

[ohcbird]

If you run the stock setup from a 4th gen, you can put a 15" wheel back there- I ran different Weld's on my 98 SS (from 15x8 to 15x10).