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Not sure I have the correct dipstick and tube. This is for a 68 GT 390. A PO blew up the original motor and replaced it with a relatively period correct (was told by the PO pre-smog, late 60's or early 70's) 390 out of ???, so could be most anything. Casting codes are too rough to make out. Motor has been completely rebuilt, and I rustled up the correct GT heads and exhaust manifolds. The tube that came with the car measures about 10-1/4". The stick PN is C7AE-6750-A. The handle has been broken off and an aftermarket handle attached. Yeah, that's what I would've done...

With the tube pushed into the block just enough to hold it in place, the mounting flange is still short of the mounting bolt on the exhaust manifold, which I believe is the correct mounting point (see photos, hope they're there - trying to figure out this resize option). If I insert the tube all the way into the block the bolting flange on the tube is about 1-1/2" away from the bolt. For my engine looks like the tube should be somewhere near 11-3/4", not 10-1/4". Interestingly, the NPD catalog lists 10-5/64" as the correct length for a 68 GT 390, so sounds like this tube should be correct. Not sure how this can be unless the position of the block hole changed with application (which sounds unlikely). I'm under the impression all 390 blocks were the same, so the only variation should be where you can bolt the tube - variations in head design and exhaust manifolds would determine the tube and stick lengths. A search of engine photos didn't help - lots of variations, and few hard facts. Anyone clear this up for me? Sure would like to make sure we're right before I fire it up for the 1st time. BTW, it was rebuilt by a very competent builder and already has oil in it.



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