J56 Brake question
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 3,717
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From: Seattle Washington
J56 Brake question
I am using a set of J56 Brakes that I have had stashed away for probably 20 years or more. I am using them with used Pads and Used Rotors. When I expand the Pads and bottom them out up tight to the Caliper Housings I'm getting 1" of distance between them. Obviously, this is not going to fit over a new 1 1/4" Rotor. I always thought that the J56 Calipers had a Spacer between the Caliper haves so that they could run thicker Brake Shoes and get more Laps before having to change the Shoes. However searching the Innerweb I'm not seeing this anywhere. Maybe it was the Aftermarket that came up with this idea. Sure looks like the Shoes I have were intended for wider Calipers. How did a J56 Car leave the factory ? Was there anything different in the Rear ? Just the fronts were duel pin correct ?
Safety Car
Joined: Dec 1999
Posts: 3,600
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From: PA
You are correct, just the front calipers were converted to dual pin. The rear calipers retained the stock single pin retention method although all four sets of calipers used the phenolic/plastic insulators on the pistons.
There were no spacers in the calipers and the standard rotors were used.
I restored a 1972 ZR-1 several years ago and what I described is exactly what was on the car. I have seen more than a few L-88s, ZR-1s and ZR-2s over the years... They were the same. Not sure what the problem is with your calipers... Perhaps incorrect pads, perhaps the caliper castings themselves have been machined, perhaps incorrect castings. What are the casting numbers on your calipers?
Regards,
Stan Falenski
There were no spacers in the calipers and the standard rotors were used.
I restored a 1972 ZR-1 several years ago and what I described is exactly what was on the car. I have seen more than a few L-88s, ZR-1s and ZR-2s over the years... They were the same. Not sure what the problem is with your calipers... Perhaps incorrect pads, perhaps the caliper castings themselves have been machined, perhaps incorrect castings. What are the casting numbers on your calipers?
Regards,
Stan Falenski
Team Owner
Joined: Apr 1999
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Ive worked on a few historic racing cars. Some pads are thicker out of the packaging. They are made for thinner rotors. We used a vertical mill on the pads to make them for thicker rotors.
Dontov motors sells j56 brakes with options call them up about pads
Dontov motors sells j56 brakes with options call them up about pads
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 3,717
Likes: 551
From: Seattle Washington
I looked at Duntov and see that they sell J56 Barke Pads in sets of 4 or 8. Thats what made me wonder if they were available for the rears. I'm sure people make their own J56 for the rears. Porterfield Brakes has a whole bunch of different compounds available for J56. I have a Bridgeport Mill and I can make the Pads I have now work. But its odd that they are used, with the marks of being used on Rotors. My Caliper Casting Numbers are correct for 1969. I had to sort through quite a few to get the right ones. But it really doesn't matter as they are interchangeable from 1965 to 1982 and all share the same dimensions. .
Melting Slicks
Joined: Nov 2006
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From: Apple Valley, MN
There seems to be two camps out there - one says the dual pins were used only in front and the other says all four corners. I’ve spent a couple hours researching old posts and can’t find a definitive answer. Can someone cite a definitive source for which is correct?
Safety Car
Joined: Dec 1999
Posts: 3,600
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From: PA
My Caliper Casting Numbers are correct for 1969. I had to sort through quite a few to get the right ones. But it really doesn't matter as they are interchangeable from 1965 to 1982 and all share the same dimensions.
As for proof:
Regards,
Stan
