1966 327 crank to 350

I was wondering if it is possible to use the crank from a 1966 327 4 bolt main and put it in a 1975 350 with a 4 bolt main


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If the crank is truly from a '66 327, it's not a 4 bolt main engine and is a small journal crank.
It CAN be used in a 350 block, but you will need to use bearing spacers due to the differences in the bearing sizes.

As johnnya says....No matter what anyone tells you, Chevy never made a factory 327 4 bolt main engine. All 327's ....'62-'67 were small journal (3.25")forged steel cranks. The '68/'69 327 used the large journal (3.48" same as a 350) crank which was usually a cast material but you could find some out of forged steel and these cranks will interchange with a 350 block. Now you can take a large journal 327 crank and install it in a 4 bolt 350 block and THEN you will have a 4 bolt 327....just not factory.....and by the way, the number of main cap bolts has nothing to do with which crank can be used in a certain engine.

3.48" is the stroke of a 350/305/267.

The journal diameters were 2" rod/2.3" main for the small journal cranks and 2.1" rod/2.45" main for the large journal cranks. The 400 is 2.10"rod/2.650" main.

Spacers w/regular inserts or thick bearing inserts can be used to fit a SJ crank into a LJ block.

Lets get a little deeper as to what you're completely doing. The 327 and 350, even for the same journal size are differently counter-weighted. While the 350 and 327 share the same center to center length on the connecting rod, there is a quarter inch of stroke difference made up on the piston pin location; plus the 66 crank would use the small journal rod, not the late 327 (1968) and 350 large journal rod. A 350 piston on a 327 crank and rod will be low to the deck at TDC by an eighth inch. So you would have to also use 327 pistons with the 327 crank or this would have zip for compression and might have collision problems between counter-weights and piston skirts at BDC.

Where is the evidence that the 327 had 4 bolt mains, it's claimed there never were any, I've never seen one; although I had a Ford 390 Police Intercepter with cross-bolted mains for which it is also claimed there never were any. So it would seem the factories don't always follow the stated rules. Given this is a 1966 it will be a small journal shaft, which will require bearing spacers on the mains, something I've never been fond of.

Bogie