Drum to Disc Brake Conversion

The Problem...

Imagine the feeling of making a 126 mph pass down the 1320 only to realize that the stock drum brakes are as bad as the old urban legends say at stopping a 3400 lb camaro. Although the drums may have been sufficient for street driving, it only took a single pass like this running off the end of a track with a very short shutdown area for me to decide to convert the project 1967 Camaro over to front disc brakes.

Purpose of this Text...

I want to help people who are thinking about a disc brake conversion realize some of the subtle issues they may not have considered. Hopefully, this will point out some of the problems you will encounter so that you can plan for them and setup a contingency plan or at least be prepared. Although it may eventually grow into a full step by step how-to, that is not the real purpose of this writeup at this time.

Kit Selection...

Since we were on a very tight time schedule both from the standpoint of acquiring parts as well as limited use of a lift, we really didn't have the time to piece together all the parts from junk vehicles... and hope they all worked properly together. We started a search for a complete "kit" for the conversion. Essentially, you can group the kits into two categories... "stock" and "not stock". The stock kits use factory parts (either new or rebuilt) while the non stock kits generally have lighter or larger (or both) specialized components such as master cylinder, rotors and calipers. Since the project Camaro is full-sized (over 3,000 lbs) and relatively-high horsepower monster with a generally streetable nature, we quickly decided on a "stock" style kit. Another advantage of the stock kits are that you can easily get replacement bearings, pads, calipers, master cylinders, etc from your local auto parts store... whereas the specialty kits generally have one-of-a-kind components that you can only get from the manufacturer, and it is generally your responsibility to piece together the right master cylinder, lines, calipers, etc.

I happened to call Master Power Brakes first, and somehow managed to get the owner. Being a very knowledgable guy, he quickly persuaded me to go with their standard front disc conversion, with upgraded carbon metallic pads. Alltogether, the price tag would normally be in the order of $950! When I questioned him on why other vendors such as Stainless Steel Brakes sold their similar kit for $700-$750, he said that Stainless used rebuilt parts while Master Power used only all new parts for everything, and that the Stainless kit isn't as complete. Hmmm. After convincing him to drop his price to the same ballpark, I bought the manual brake kit.

Some More Data...

Although some things the MP guy said proved to be questionable, some things he pointed out from his years of experience are worth noting:

1. The first thing he pointed out is that a stock drum brake master cylinder is grossly inadequate at pushing the added volume of brake fluid needed to operate disc brake calipers. Be weary of kits on the market that sell you the rotors/calipers but don't include a master cylinder.

2. Putting disc brakes on the rear of a car like the project Camaro (*) is a waste of money since the fronts do most of the work. He also said that generally when converting the rears to disc that much time is needed to properly adjust the proportioning valve to prevent the rears from just locking up on hard stops. He sells the rear disc kits, but really doesn't recommend it for street and most street/drag racing applications.

3. I was also convinced by the owner of Master Power Brakes that no company had spent as much time engineering/debugging brake systems as the General himself, so going with stock replacement parts (for a factory-style install) were a safe bet.

The Master Power Kit...

Pulling all the parts out of the boxes we noticed how heavy duty (and heavy!) all the parts were, which convinced me to go ahead and order the Fat Man Fabrications tubular A-arms... but that's another article. The first thing you notice is the monsterous Corvette master cylinder. Anyone wishing to keep a "factory" or "pure stock" appearance should consider this when evaluating the different kits. Everything appeared to be complete and in order including bearings, races, spindles, rotors, brake pads, new frame-to-caliper lines, caliper brackets, wheel bearing nuts, master cylinder, combination valve and master cylinder-to- combination valve lines. Once the A-arms arrived, we were ready to do the install all at once.

The Install...

Although we have all done suspension work before in gravel driveways with k-mart tools, I sure wouldn't recommend doing that if there is any way to avoid it! We had about 5 days of Jon's shop to install a 10-pt cage, do the front suspension and brake work and install a new set of gears in the 12 bolt rear. Needless to say, the brake/suspension work would have taken much longer without a lift and full access to power tools.

Most of the ordering isn't critical, but here is the procedure in a nutshell:

1. car on lift & jack under lower control arm ball joint

2. remove wheels, brake drums and shocks

3. Separate tie rod ends from spindles with pickle fork

4. Disassemble drum brake mechanism... remove movable parts

5. Disconnect brake lines from frame mount & plug frame mount lines to keep brake fluid from pissing all over everything

6. Separate lower control arm ball joint from spindle with pickle fork... make damn sure jack is secure under control arm since force of the coil spring will force the lower control arm down

7. Slowly and carefully lower jack until lower control arm reaches bottom of travel - spring should just pull right out. (*)NOTE!!! some people find this very dangerous (myself included) so be very very damn careful when dealing with coil springs under pressure. A "proper" way of doing this is to install a spring compressor on the spring, seperate the lower ball joint, remove the still-compressed spring. You should follow your specific car's service or shop manual here!

8. Separate the upper ball joint from the spindle

9. Now that everything is apart, it is a good time to replace the a-arms or replace the bushings and ball joints in your existing control arms, clean/paint the frame, a-arms, springs, and other parts you would have difficulty reaching with the suspension in place. Go ahead and check the tie rod ends while you're in there too. Since we knew we would be taking some weight out of the front of the car, we went ahead and cut a coil out of the stock springs... boy did that drop the front end. Be very conservative when cutting coils out... in fact, the rule of thumb is to go in 1/4 to 1/2 coil increments. It's a pain to put it together and pull it back apart, but it will save you from dropping it too far. I believe the conventional wisdom is about 2-3" drop per coil removed. If you are going to cut it, don't use a torch... use a buzz wheel, hack saw or even circular saw instead.

9.5. This is where we installed the beautiful new FatMan tubular A-arms. Wow! For $700, you get all 4 control arms, set up for exact factory dimensions and locations, with provisions for factory sway bar, shock, etc. They come with a nice flat black powder coating that is very durable, and new balljoints and bushings already installed. They are literally about a 5 minute bolt-on at this point. (BTW, they save about 15 lbs of weight over the stock units, are much more rigid, and look ultra groovy too. Can you tell we like em?) NOTE! You may have difficulty getting the upper control arm rail due to interference with headers or steering linkage. The studs that locate the rails are lightly pressed into place and can be (carefully) tapped out with a light hammer once all other things are unbolted and ready to remove. Try to keep the alignment shims organized as you will need to put these back where they came from!

10. Remove old master cylinder, being careful to stuff plenty of rags anywhere you _don't_ want brake fluid to go!

11. The install of the new disc brake kit is pretty much reverse of the removal, with a few minor :-) exceptions. You will need to assemble the new hubs, run/modify the brake lines from the master cylinder down, etc.

12. Don't forget to thoroughly bleed all brake lines and getting an alignment is a good idea too anytime you make chassis component changes.

(This is where chilton's would quit on you, but we're going to save you some frustration!)


1. Do NOT assume that your existing brake lines (from master cylinder to frame mount/wheel line intersection) will work! In fact, go ahead and buy/borrow a brake line flaring tool, a handful of misc size brake lines with pre-made ends and different size fittings. Oh yeah, don't forget a small tubing bender tool. The MP kit has a combination valve that mounts on a small bracket that bolts along with the master cylinder onto the firewall. MP includes the short lines that run from the master cylinder to the combo valve, but even these had to be bent. I also had to drill an extra hole in the combo valve bracket so that it would work on my firewall. If I didn't have to plumb in a line lock, I might have gotten away with merely bending and/or changing the fittings on the existing lines, but since I installed a line lock, the routing/bending/profanity part of the brake lines actually took the most time of the whole project. This is where a little fabrication work comes in handy, but even the novice can get it done with some patience.

2. All the parts come nicely painted, or so you think. Imagine how pissed I was when we got to the Memphis '97 f-body event to find that just about everything had a nice coating of bright red RUST on them! GRRRR! Whatever you do, don't believe that the nice factory-looking gray paint is going to hold up! Follow your favorite painting procedure (scotchbrite pad followed with some thinner on clean rags and a tack rag should be OK) and paint to your heart's content. Eastwood sells a nice factory gray-looking paint that would work fine. I ended up going back later (which made for a great big pain) and painting everything the best I could with some good brush-on black enamel. I wish we would have known... sigh. Things you should paint? center part and of the rotors (where the brakes don't sweep), the spindles, calipers and the master cylinder. The caliper brackets are a nice anodized finish and don't need paint.

3. Some parts are missing! Before you chuck all your old drum stuff in the can (you wouldn't do that?), you will need some of the small fasteners that hold the caliper brackets to the spindles. Oh, the kit also doesn't contain the disc brake backing plates! These things are around $100 ea though your 1st gen suppliers, but since I don't drive on the street too much, I didn't bother getting them. We also didn't realize they were missing from the kit until we were jamming on the project which was a bit of a bummer.

4. Some parts sure didn't look new! The spindles that came with my kit were nice and clean at first inspection, but when it came time to install the wheel bearing nuts, we noticed that the threads on the end of the spindles were slightly buggered up. Grrrr. We hit 'em with the proper size die to clean them up, and they worked fine. Would have been a trip to the HW store had we not been at my bud's shop.

5. Oh yeah, you will also need to assemble the hub... that means pressing in the races, getting the bearings in there correctly etc. You can consult any shop manual and see the proper way to do this... but just something else you may want to think about while doing your homework. The hubs already have the stock type wheel studs installed, so that's one less thing you have to do... unless you have to go to the trouble of installing long NHRA legal 3" studs. Whew, what a mechanical bunghole that procedure was. Don't forget to get the larger .560" knurl as opposed to the smaller .480" knurl studs if you do this.

6. The factory disc brake spindle/rotor combination places each wheel 3/4" outboard of where the drum combination places them. Make sure this won't be a problem with your wheel/tire combination. FatMan also makes/sells spindles and other a-arms that will keep the drum geometry. There are also disc brake kits (such as from Wilwood) that reuse the stock drum brake spindles.


The entire process only took a couple of hours, and would have been half that except for the brake line fabrication. Would we recommend the kits again? The FatMan A-arms are beautiful! I wish we could have gotten them through a group purchase since the $$$ is steep. I would think twice about the Master Power kit, though. It didn't quite live up to my expectations, but again maybe that's because I've never looked at any other full kits before. It stops a magnitude better than it did before, so I don't worry about being able to shut down after a full 140 mph bottle pass. Be patient, do your homework and good luck!


Jonathon Lusky sent me the following message about the Stainless Steel Brakes Kit: (printed with permission) Hope this helps!

I saw your page on the 67 swap with the MP kit. I'm almost done installing a SSB power disc kit on my 68. The kit was pretty much complete except for the lines for the master cylinder & prop valve needing to be trimmed down and reflared (the included ones are about two feet long). It even includes all new bolts. The MP kit includes an adjustable prop valve that goes between the m/c and the stock distribution block. The stock distribution block happens to occupy the same point in space that part of the booster wants to, so I flipped it over its forward end and rebent the front and rear lines to match up. I ran into a couple of quality issues with the kit:
- The left caliper bracket wasn't square to the rotor. It was about .020 closer at the top than the bottom. Pad wouldn't even fit in it.
- The backing plates rub the rotors, I had to knock down a "corner" a bit with a hammer on both plates.
- The rod coming out of the rear of the booster wasn't threaded well, had to chase it with a die to get the clevis (or a new nut) on. The scary part is that it already had a jamnut threaded on it that spun easily (that jamnut also fit my original master cylinder fine, so I'm fairly certain the threads are the "same").
- The instructions supplied are terrible. Probably the funniest screwup is that bolting on the steering knuckles is several steps before installing the backing plates and caliper brackets--the steering knuckle bolts also attach those.
- everything was packed in shredded waste paper (old printouts, documents). It was all mildewed and stunk up the whole office when I opened a box at work. Had to take it outside to unpack it all. And there were little bits of shredded paper stuck to everything and up in every nook and crany of anything that wasn't in a plastic bag.
The quality of the booster and hydraulic parts are yet to be determined, they are all clearly rebuilt units.


Been a while since I updated this page. Anyway, the master power kit is long gone. I installed a wilwood "heavy" front drag kit on the camaro a couple years ago. The kit replaced the rotors and calipers, but included everything needed for the conversion. The swap dropped a whopping 40lbs of weight off the nose of the car. Everything was very nicely organized and packaged. BTW- I've gotten a couple emails over the years since originally writing up the master power install that people have gotten much better quality in the packaging of the parts sent by MP. Overall, I'd say you can't go wrong with any of the major kits. Good luck!


Name : Fat Man Fabrications (FatMan)
Type : business
StrAddr : 8621 Fairview Rd
CtyStZip: Charlotte, NC 28227-7662
Phone : 704-545-0369
Fax : 704-573-0401
Group : automotive-parts
ContDate: 970515
Notes : custom front suspension; tubular a-arms; control arms, etc

Name : Groves Automotive (Wild Willy's Racing Engines)
Type : business
Contact : Groves, Jon
StrAddr : 521 Rorer Ave.
CtyStZip: Roanoke, VA 24016
Phone : 540-345-7519
Group : automotive-service
Notes : fabrications; welding; full service; reasonable rates

Name : Master Power Brakes
Type : business
StrAddr : 254 Rolling Hill Rd
CtyStZip: Mooresville, NC 28115
Phone : 704-664-8866
Fax : 704-664-8862
Group : automotive-parts
Notes : disc brake conversion kits, lines, calipers, etc.

Name : Stainless Steel Brakes
Type : business
StrAddr : 11470 Main St
CtyStZip: Clarence, NY 14031-1779
Phone : 716-759-8666
Fax : 716-759-8688
Group : automotive-parts
Notes : disc brake conversion kits, lines, calipers, etc.

Other vendors to consider... Brembo, Baer Racing, Vette Brakes, Wilwood, etc.

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