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Discussion Starter #1 (Edited)
Doing this right now on a 68 El Camino. Same principles and parts as drum brake first gen Camaro.

I bought a disc brake booster and mc for ridiculous cheap on CL. Brand new MC with lifetime warranty. The guy put it on his 68 Chevelle and his fancy wheels wouldn't fit, so he bought a complete Wilwood kit.

Cheap Big Brakes

Very straight forward following the guidlelines set out on David P's web site.

Wanted to ad that you will need to source a new bolt for the top of the bracket. The drum brake bolt doubles as the anchor pin for the drum brakes.

Also wanted to ad that if you find a set of backing plates cheap (I did.... they came with the used 69 style caliper brackets I am modifying... paid $80 free shipping for caliper brackets AND backing plates) you can use the 69 Camaro or Chevelle dust shield. You just need to make a lot of cuts along the perimiter to flatten it out just a bit. If you aren't worried about looks (who is going to see your dust shield anyway?) it works just fine.

One other thing; I didn't see this in the write up, but just to make sure everything fit perfectly, I had the "additional" metal drilled an bolted to the spindle before tacking the caliper bracket in place. Then took it back to the bench to make sure everything was square and lined up perfectly. I didn't want to have to wallow out the bolt holes even a little bit. Everything fits tightly that way.

Also, when you order calipers and brake hoses, don't forget to order two banjo bolts (I didn, so now I have to wait a few days to get this on the road).

Now, if I can just find someone with a mid 70's Buick or Olds with 11 inch rear drums they are parting out..... I would be set. Plan to use the El Camino as a tow vehicle from time to time, so that is why I went with the Corvette front rotor and truck calipers.

MANY THANKS TO DAVID POZZI FOR POSTING THIS PROCEDURE. I will have less than 1/3 of the cost of aftermarket brakes, and it will be serviceable with all GM parts.

This is a really fun procedure if you can do light fab work and have a good welder. I did not send the spindles to be machined. I measured carefully and cut it with a hack saw, cleaned it up with a large file. Hey, I needed the exercise anyway, and this is better than the gym. Plan on wearing out a good Lenox hack saw blade per side before it is all said and done.
 

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Awesome! So much of this hobby has devolved into buying Lego kits and snapping them onto a car. Great to hear about your project. I don't envy you sawing off the bosses with a hacksaw!

If you don't need an internal parking brake, it may be just as easy to fit calipers on the rear as it is to upgrade the drums.

I finished up a scratch built JL-8 system and while it was a pretty challenging project, the braking performance is phenomenal and I have a lot more faith in GM parts vs. aftermarket consumer stuff.
 

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Doing this right now on a 68 El Camino. Same principles and parts as drum brake first gen Camaro.

I bought a disc brake booster and mc for ridiculous cheap on CL. Brand new MC with lifetime warranty. The guy put it on his 68 Chevelle and his fancy wheels wouldn't fit, so he bought a complete Wilwood kit.

Cheap Big Brakes

Very straight forward following the guidlelines set out on David P's web site.

Wanted to ad that you will need to source a new bolt for the top of the bracket. The drum brake bolt doubles as the anchor pin for the drum brakes.

Also wanted to ad that if you find a set of backing plates cheap (I did.... they came with the used 69 style caliper brackets I am modifying... paid $80 free shipping for caliper brackets AND backing plates) you can use the 69 Camaro or Chevelle dust shield. You just need to make a lot of cuts along the perimiter to flatten it out just a bit. If you aren't worried about looks (who is going to see your dust shield anyway?) it works just fine.

One other thing; I didn't see this in the write up, but just to make sure everything fit perfectly, I had the "additional" metal drilled an bolted to the spindle before tacking the caliper bracket in place. Then took it back to the bench to make sure everything was square and lined up perfectly. I didn't want to have to wallow out the bolt holes even a little bit. Everything fits tightly that way.

Also, when you order calipers and brake hoses, don't forget to order two banjo bolts (I didn, so now I have to wait a few days to get this on the road).

Now, if I can just find someone with a mid 70's Buick or Olds with 11 inch rear drums they are parting out..... I would be set. Plan to use the El Camino as a tow vehicle from time to time, so that is why I went with the Corvette front rotor and truck calipers.

MANY THANKS TO DAVID POZZI FOR POSTING THIS PROCEDURE. I will have less than 1/3 of the cost of aftermarket brakes, and it will be serviceable with all GM parts.

This is a really fun procedure if you can do light fab work and have a good welder. I did not send the spindles to be machined. I measured carefully and cut it with a hack saw, cleaned it up with a large file. Hey, I needed the exercise anyway, and this is better than the gym. Plan on wearing out a good Lenox hack saw blade per side before it is all said and done.
Pictures, or it didn't happen! :p

I am really interested in this. I also read David's article, although he said this was just a mockup, and he never actually got it working on a vehicle. I will be looking forward to reading about your results.

Could you accomplish the spindle modification with an angle grinder and/or a sawzall?

Wouldn't the 11-inch rear drums also be on the mid-70's Caprice Classic and full size station wagons? What about pickup trucks?
 

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I finished up a scratch built JL-8 system and while it was a pretty challenging project, the braking performance is phenomenal and I have a lot more faith in GM parts vs. aftermarket consumer stuff.
What did you do about caliper brackets? Did you buy a set of stock JL8 brackets? That has been the big hold-up for me - even the reproductions are ridiculously expensive.
 

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Discussion Starter #6
I found the caliper brackets with backing plates on ebay a few months back. You have to modify the standard bracket as set out in the article to move them out 3/8. They come up from time to time.

Yes, most full size Chevys of the mid 70's have 11 x 2 rear drum brakes. Don't know why I said Buick or Olds. The Chevy rear brakes would work fine.

I will take pics tonight if i don't forget.

Could you accomplish the spindle modification with an angle grinder and/or a sawzall?
Yes you could. I have gotten pretty good with a hack saw on stuff like this. Just took about 5 minutes to cut off. Angle grinder would sure create a lot of metal dust!
 

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Thanks for the feedback. The only downside to this setup is you have to weld on caliper brackets which is a bit scary. If the welds are good quality, then it makes a very inexpensive setup that should work very well.
 

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Thanks for the feedback. The only downside to this setup is you have to weld on caliper brackets which is a bit scary. If the welds are good quality, then it makes a very inexpensive setup that should work very well.
I have a buddy that works at a professional welding shop that does a lot of fabrication. If I decide to take on this modification, I will probably tack weld it and run it out to him for the final welding, just to be safe.
 

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What did you do about caliper brackets? Did you buy a set of stock JL8 brackets? That has been the big hold-up for me - even the reproductions are ridiculously expensive.
I don't want to muck up this thread and cause confusion because we're talking about two different systems but... I bough cheap repros a few years ago. They fit very poorly and I have a lot of manual milling into them. If I did it again, I'd put the money into the currently available (expensive) repros. Because nothing on the bracket is co planar, building them from scratch is near impossible. Rear mounts are stock vette parts that i adapted with a custom bracket.

I owe camaros.org a summary of what I did but I've been hesitant because I didn't take as many pictures as I should have and my drawings are pretty crude. Someday..
 

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Discussion Starter #10
Got the right side done tonight. Pics will have to wait til tomorrow nite. It is almost 11 pm and this ole fart needs to go to bed.
 

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Got the right side done tonight. Pics will have to wait til tomorrow nite. It is almost 11 pm and this ole fart needs to go to bed.
Sounds awesome, Lynn. One thing that interests me about this upgrade is that you get all the advantages of the larger rotors without moving the wheels outboard as far as the factory disc rotors will do. Looking forward to seeing those pics and hearing about your results!
 

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Hey David,

The pictures of the caliper bracket appear to show the metal plates that were used to relocate the bracket 3/8" further out to be welded on the face of the bracket. In other words, it looks like it will space the brackets inboard by the thickness of the plate, unless some type of spacer is employed. Am I seeing that right, and if so, does it cause any issues with caliper / rotor alignment?
 

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They need to be flush on the spindle face, and I think they are pretty close to that but it's hard to see, maybe it was built up with weld. You don't want to move the bracket in or out. Just outward radially 3/8" to compensate for the 3/4" larger OD rotor.
 

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Discussion Starter #15
I agree, the above pics make it look like it was just welded on top.
I cut out metal and inserted 1/4 inch thick tabs in the opening.
First cuts were made with the hacksaw (really starting to hate that thing.... hmmm, may be time to by a big time band saw) and the side to side cuts were made with a sabre saw on very low speed. Still wore out a few blades.

Not many pics tonight. I have a very complete write up almost ready to go, but left it on my computer at the office. Tomorrow nite wiill be more complete, and I will answer more questions. Did get the booster and new master fitted tonight. Have to buy a new brake line from the master to the distribution block. Old one isn't long enough. As you can see, this is a GS (grimy sucker). It is a driver. The old engine leaked oil from everywhere. I didn't even bother to clean up parts when I rebuilt the front suspension.
 

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Looking good, Lynn. I think this is the direction I am going to go on my 67. I am thinking that I will make my inserts with the new holes ahead of time, and then make up a jig to mount the bracket on and use the inserts to scribe the metal that will be cut out of the bracket.

A thought crossed my mind - can the same thing be done with a set of 67/68 caliper brackets and then mount a set of the C3 Vette calipers on those? I already have a set of the 67/68 brackets, and C3 calipers are pretty easy to find. The only catch I can think of is that there might be some offset issues going from the stock rotor location to where the Vette rotor would end up mounted on the drum spindles. The same issue may be present with the single piston caliper, but that is a sliding design that might be able to compensate for this.
 

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Looking good, Lynn. I think this is the direction I am going to go on my 67. I am thinking that I will make my inserts with the new holes ahead of time, and then make up a jig to mount the bracket on and use the inserts to scribe the metal that will be cut out of the bracket.

A thought crossed my mind - can the same thing be done with a set of 67/68 caliper brackets and then mount a set of the C3 Vette calipers on those? I already have a set of the 67/68 brackets, and C3 calipers are pretty easy to find. The only catch I can think of is that there might be some offset issues going from the stock rotor location to where the Vette rotor would end up mounted on the drum spindles. The same issue may be present with the single piston caliper, but that is a sliding design that might be able to compensate for this.
I did that exact swap in the early 70's. The corvette caliper bolt spacing is different but not far off. I don't recall much else about it.
 

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Discussion Starter #18
So, guessing you all know what drum brakes look like.
Here is the before shot.
As you can tell, this isn’t a resto. This is a driver. When I rebuilt the front suspension, I did not worry about cleaning up the parts. The old engine & trans (307 PG) leaked profusely, which is one reason the vehicle is 99.9% rust free. Oil everywhere. PS box still leaks, but will get replaced soon.

This is a 68 El Camino. However, everything will be the same on any drum brake first gen camaro.
Probably not worth doing this to a disc brake car, as the factory disc brakes are good enough for street cars. However, those parts are getting hard to source, so this works out pretty well going from drum to disc.
 

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Discussion Starter #19
So, here is the spindle in the vise. You can see the boss that needs to be shortened. Notice the first ½ inch of the hole is not threaded. The alignment anchor pin for the drum brakes goes in this hole and has a shoulder that fits tight in the unthreaded portion. I believe David’s article says to remove .610. I did that on the left side, and it worked out perfectly. Just to check, I bolted the caliper bracket in the boss (before shortening the boss) and measured the gap between the bracket and the lower mounting hole (which doesn’t get shortened. I used a snap gauge (you can barely see it in the last pic). And put a mic on it. .607. So, are we really off .003? I doubt it. These brackets are just stamped steel. We aren’t setting ring gaps. The MAIN thing, in my opinion, is to make sure the brackets stay square to the spindle. It is a floating caliper, and will auto adjust for a few thou either directions. What it can’t do is square itself.
 

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Discussion Starter #20
You can see the boss to be cut off in one of the pictures above. Measured .610 and scribed it. I intentionally cut off a little less, so that if I did not stay perfectly square, I could square it off with a grinder or file. Fortunately, all I needed was the big a$$ file. I really wasn’t worried about taking off a little too much. It would be very easy to shim it out. I did not need shims on either side. You would have to fubar it pretty badly to ruin it.

About 80% cut through. Looks daunting, but I timed this one. Even with the break for photos, it was 7 minutes. Way shorter time than a trip to the machine shop.

Fist thing is to bolt the bracket (unmodified) into the existing holes and make sure your bracket isn’t bent. Take careful measurements. I measured both holes from the caliper alignment tab AND each hole from the mounting pin threaded hole. As pointed out in David’s article, you want to move the two mounting holds 3/8 farther out (or depending on how you look at it, 3/8” further in). The point is to get the bracket 3/8” farther out so that the big truck caliper will fit and not hit the rotor.
 

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