[chemnick]

Hey guys:
(I have this on GTO Forum also)I have all new parts for my 4 piston disc brakes together on my '67 and the caliper (bolted on tight) is about 1/4" off center (outboard) from the disc. Also, the 14" Rally II's JUST BARELY hit on the caliper. Bearings/races are new, as is the hub/disc. Seems that if I could shift the hub location with different inner bearing/race or spacing it outboard at the spindle, life would be good. I expect this may cause the grease seal to no longer align with the spindle shoulder also. Anybody been there before or have an opinion? Thanks.

[chemnick]

Here it is.................................

[GT182]

I've never played with the 67 4 piston calipers, so this is just a thought. Can you use washers on the mounting bolts to move the caliper over so it aligns properly?

As for the caliper rubbing on the wheel .. or barely rubs as you say... you can file down the high spots so you have more clearance. I've heard and have read that you can grind off the high spots and it won't harm the caliper. But if you use a grinder disc don't let it build up any heat and cook the brake fluid.

[george kujanski]

I believe I read somewhere that OEM 4 piston calipers needed 15" wheels...

George

[ClassJ]

I would have to look but I believe the offset is normal.

Regarding wheels. The 67 and 68 disk brake cars used rallye II wheels with different centers. All of the reproductions I am aware of are based on the drum centers. I would call Ames or PY and discuss.

Also the steel wheels for 67 were unique on disk brake cars. I believe the Rallye I wheels only had one center type that cleared disk and drum.

[chemnick]

Thanks for the info. At this stage of the game I may just try to seek out some 15" Rally IIs. Can't space the caliper mount or backing plate over because each piece in the assembly mounts outboard of the previous so this would move the caliper in the wrong direction. Were it not for that, I'd give it a try. I guess I could try putting a washer or two onto the wheel studs prior to the wheel just to get a reference how much I would have to remove from the caliper body to gain the clearance I need.............

[Kenth]

GTO steel wheels w/Disc Brake have code HF, 14 x 6". (Drum brake code A).
(Service Manual says HB for disc and G for drum brakes?).
GTO Rally II w/Disc Brake have code JA, 14 x 6". (Drum brake code JC).

Diameter on all wheels is 14", except Fullsize models equipped with Disc brakes and certain heavy-duty options have a wheel diameter of 15 inches.

[chemnick]

I took the hub off to see the spindle and where the grease seal ride on it just for kicks. While I was checking things out it seems that if the disc where it meets and bolts to the hub were 1/4" turned down that much more, life would be good. At that point I wondered if there were other two piece assemblies which bolt together the same way and did the guy who put this together maybe get the wrong disc half??? I wish I could get a detail drawing of the correct disc to double check the total height of the disc................I'm gettin' too old for this ****

[GT182]

Originally Posted by chemnick

I'm gettin' too old for this ****

You are not alone in that. Quit reminding us LOL

I'm sure someone will get you a photo soon. Hang in there.

[chemnick]

I am still trying to see if I'm going to be able to work things out with these brakes. I have another issue that perhaps I can get some info on. While taking the pics that are attached below (I hope) I noticed that the brake line connection looks to be set up for banjo bolts. The new caliper side steel lines clearly are not, I tried the jumper lines in the connection just to see if the threads were the same but they don't appear to be unless the threads are burred slightly. I am trying to find out if there is supposed to be some sort of adapter which might be missing from the calipers. I have established that the casting numbers of both the inner and outer halves of the calipers are correct and they do bolt right up to the backing plates and sit in the correct position. Any thoughts?

[chemnick]

So, I returned to the rebuilder of my 4 piston calipers to see what might be figured out there. Some interesting stuff. Turns out my calipers are an exact match for 1968 Camaro fronts (even with the banjo bolt type connection). Now I'm thinking that maybe a set of Camaro front flex lines will do the trick. The guy there tells me there are some cases where they use a "block" fitting on the fluid line connections to make a transition from banjo to steel line connection. Oh, maybe just some block fittings will do. Then he takes my calipers out back to see what there might be that uses the same castings but has a flare (steel line) connection built into the caliper (very obliging fellow). All he came up with was a 60's to 80's Corvette rear disc caliper, although the pistons were smaller. Perhaps Camaro calipers are more valuable than GTO.

Someday when I'm old(er) I'll write a book about this. A sure million seller.
Chemnick

[marxjunk]

ive had a bunch and ive sold a bunch..i grab all i can find..heres what i know..

67 is 67...68 is 68...minor diff but diff,,of course camaros are more valuable,,,lol

you cant mix and match..all 67 or all 68...PERIOD

a-body and F-body calipers are the same....67 is 67...68 is 68

they did change the hard lines from 67 to 68

if anything is the wrong year it screws up the whole thing

camaro brakes bolt on to GTOs and reverse...the spindles are the same...they just flipped the bolt on steering arm at the tie rod..

69 disc spindles will really screw up alignment..the caliper braket spacing is diff

just because one is right, doesnt mean you didnt stumble into a pair of mismatched.


i know this sounds silly, but ive done it before....the bleeders are up to the top...right? it happens, especially when ya get frustrated...if one is up and one is down..you have a pair of the same..its happened to me...i cant sya ive done it on 67-8s but ive done it on 69 ups..and ya feel silly...but its an easy fix

[bammbam]

What rotors are you using? I know you said the wheel is rubbing, but the reason I ask is that I had a similar problem when I did mine. At first I used the repop 1 piece rotors supposedly made to fit 67 4 piston calipers but they rubbed and no shimming or spacing would work. ended up with the repop 2 piece rotors. Original 14" JA RII wheels will work and are what came from the factory in 67

[squidtone]

Hello Chemnick
I was conversing with you on the other forum, but I thought I'd make another response here. I was perusing my old pictures, and I found a picture of what the 67 set up should look like. 68's were quite different from what I can see in the GTO Zazarine book. Not sure at all about what a Camaro or Firebird would look like. To make things worse, these brakes were also installed on Impalas and full size Pontiacs....

Anyway, here is what the 67 A body should look like. (see picture I found from my rebuild a couple years ago) The caliper casting does have an internal "flare" that the brake fitting mates the flared line to. I don't remember if the male flare is machined into the cast iron, or if it is a brass insert. If I had to guess, I'd say it is just machined into the cast iron.
It's hard to see in the picture, but my caliper was spot faced on the casting where line goes in. The spot face was meant to proceed with the machining operation (I guess) to machine in the thread/flare shape, etc, to have a flare fitting brake line.
Note the "L" shape/hockey stick shape shorty brake line. Obviously the other end screws into the brake hose suspended by the bracket.
So, anyway, it's another page for your book! Sorry you're having so much trouble...it's just a case where you've got a variety of parts from who knows where.

P.S. I just looked at your picture of where the brake line goes in....the hole in your caliper is definitely closer to the outer edge and a bit down. It also looks bigger than the casting I have.... Compare the locations....

[GT182]

OT... Dave, I like your website..... nice! And the link to Auto Gear in Syracuse too.

And now back to the regularly scheduled Thread by Chemnick . Sorry I went OT Chem.

[squidtone]

Thanks GT182!