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J56 68-75

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Old Oct 28, 2014 | 03:57 PM
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Default J56 68-75

Can somebody help by confirming that if you have the option J56 it is with J50? and both front and rear are Twin pin calipers included in that package.
The reason being on a L88 I had always thought both front and rear ,however in another thread on question a gentleman who said he had a J56 optioned 427/435 car it was only fronts thus making me think only race corvette's(L88) were given rears. please help solve thank you for any help in this matter. Mick from UK
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Old Oct 28, 2014 | 04:39 PM
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here are the rear, I believe J50 was mandatory when ordering J56
http://www.ebay.com/itm/like/271639569289?lpid=82

Last edited by MelWff; Oct 28, 2014 at 04:41 PM.
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Old Oct 28, 2014 | 05:04 PM
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From: cambridgeshire
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Now there's a person who saw them just like me! BUT on a thread running on here someone is having a L88 done at a company who has done many L88's and they are single pin calipers on rear . And some one else claims that to be Correct ! on a L88 and 427/435 with the option. BUT clearly from the ad your posted they should have them as J56 rear twin=pins and RARE. So TWIN PIN REAR or SINGLE PIN =J56 on any yr any model
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Old Oct 28, 2014 | 05:21 PM
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I believe J-56 rear calipers were single pin from the factory but had insulated pistons, racers would make their rears dual pin for ease in maintenance, same pad front and rear.
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Old Oct 28, 2014 | 11:19 PM
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J-56 rear calipers are only single pin! They do have the super thick Pyrotex insulators on their pistons. The 80 L-88s in 68 had the adjustable proportioning valve/bracket. It is common to see the calipers destroyed from a restorers standpoint by racers who fit dual pin pads to them.
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Old Oct 28, 2014 | 11:21 PM
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Originally Posted by MelWff
here are the rear, I believe J50 was mandatory when ordering J56
1967 1968 1969 1970 1971 1972 Corvette Original J 56 RARE Rear Calipers and Pads | eBay
Those are worth about $600 for parts to a restorer

$800 to a racer
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Old Oct 29, 2014 | 12:32 PM
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Very interesting so if the Gentlemen of recent post are correct ,and who is this limey to question .
J56 option is twin pin frt & single pin rear, with a portion valve & J50. However if you do a bit of racing with your L88, you(the racer) would have them(calipers) machined to take twin on the rear. Have I got that corrrect
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Old Oct 29, 2014 | 06:39 PM
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I've checked with several very credible sources. Factory J56 rear calipers were single pin.
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Old Oct 30, 2014 | 12:22 AM
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Default J56

That is correct for 68s---69 did not have the proportioning valve. The 69 AIM shows a picture of it---and states cancelled. We researched and found a low mileage original car in a collection and he sent us some pics---the brake line setup looks like a standard 69 with power brakes.
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Old Oct 31, 2014 | 03:05 PM
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From: cambridgeshire
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I would like to thank all for their input and say that the knowledge held on this forum is unequalled.
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