Trans Swap

320Special · 09-24-2005, 09:27 AM

Hi:

Wish to set up my 1952 320 with a manual transmission, but the cranks are set up only for automatics (since 1948). A fly wheel will bolt up, if the bolt holes are reamed and relieved but this weakens the fly wheel, and I'm not sure that it's safe (bolts on the automatic for the flex plate are actually larger than those used on the earlier manual transmissions(?)) but the spacing is identical. The bell housing also bolts on so there is no problem here.

So, what do I have to do to get a 1937-1947 crank to fit. These had babbited mains I believe and the later ones were all inserts. Do they drop in or can they be machined to fit? Rods should be okay as they are all insert aren't they?

If you can help me out here, I'd really appreciate it.

**jerry burger** · 10-10-2005, 10:26 AM

the 320 cranks from 36 to52 have the same size rod and main journals.in 49 after some 5000+ engines they were converted to insert type rod bearings.the mains are already inserted,and the later rods will mate to the pre 48 crank with no problem.i performed this job on my 41 century and it works great.

320Special · 10-10-2005, 12:33 PM

This is to thank you Gerry Burger, for that information. I can get a '42 crank and drop it in the 52 block, use the 52 rods and know that it will bolt up to a fly wheel properly. Great and I appreciate that information very much. I half suspected it, but it's always best to know before you go.

Grant.

**jerry burger** · 10-10-2005, 05:42 PM

you are certainally welcome for the info.a little on the tranny`s.they are pretty much the same with minor modifications from 40 to50 or 51 (the last year of the stick for the 320).parts from 49 to 55 olds and 55 to 57 pontiac will work.i understand they have the same gears,but the case is different to accomodate the open housing on yhe olds and pontiac.good luck