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Discussion Starter · #1 ·
Anything special about a 68 J code coupe. I may be crazy, but it seems that I read something on hear and someone was saying that they had a J code and that it was special because of that? Maybe not, but I was thinking so...
 

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The J code engine in '68 (302 4v) was a little different. Basically it had different heads/intake/carb than the standard 302.
Justin
 

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A "j-code", refers to the engine, the car was originally equipped with. 1968 was the year Ford, first offered the 302. They used this year to transition from the 289 platform, to the 302. The "J-code" was the strongest, and newest of the small blocks offered, at that time. If you look at the VIN numbers of a Mustang, you'll notice the 5th digit to be an indicator, for the engine equipped with the car. In 1968, A letter "T"= 200 c.i. six cylinder.... "C"= 289 w/ 2bbl...."F"= 302 w/ 2bbl.... "J"= 302 w/ 4bbl...."R"= 428 Cobra Jet...."S"= 390 w/ 4bbl...."W"=427?...."X"= 390 w/ 2bbl.....

Are they special? Thats something you'll have to decide for yourself...... But, I really enjoy mine. :burnout:

J.R.
 

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Discussion Starter · #4 ·
Thanks guys! I think that the engine is still original, but I know the intake was not...it had a 2bbl intake from a 74 on it, D4xx. When I changed my valve covers the heads had 4V stamped on it and when I changed the intake, the engine had 302 stamped on it. Would these heads be worth rebuilding when I redo my engine, which will definately be a budget rebuild, or would money be spent better on a different head. I would only want about 300 rwhp...
 

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Check the date codes on the block and heads to make sure you still have the correect "J" code engine. Also there should be a vin stamped on the rear of the block. You might have a 74 truck 302 instead based on the intake ID.

As far as being "special" I thnink that they are. It is a sweet little engine with real good performace (same as the 68 GT-350) and in my opinion vastly under-rated by most.
 

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Shag's a J code but I don't plan to rebuild the engine just to keep it that way.
 

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I think the key to the J code's good performance was the 10:1 compression ratio due to the small chambers in those heads...Other than that the heads are nothing special though...If you would like to keep the J code motor together I would clean up the ports and you should be able to meet your 300hp goal...If you don't care about keeping it original there are much better heads out there.
 
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