'69 307 to 350 swap

[black75098]

Hey all,

First time on. I have a 69 c-10 swb w/ 307 and powerglide. I need to know what to do. I want to work on it myself instead of paying to have it done. Besides it would be alot more fun! Most people say to get a 350 and a th350 or th400. Right now the motor runs fine, the transmission is leaking like a stuck pig, and needs to be rebuilt or replaced. Local estimate on trans rebuild is $500. But my gut tells me to replace with an upgrade. Will a th350 work with my 307 without having to change driveshaft? Please help!

[a.c.ward]

TH350 AND POWERGLIDES have different lenght tailshafts.. the way around that is to use a different driveshaft.. there are many auto reclaimation yards (fancy PC words for junk yard) around Plano and DFW area... should be able to find one pretty cheap. I think that I paid $45 for the one I found at Pick-n-Pull in Dallas... pretty much easy change out from 'glide to 350... bolt on, nothing different oother than driveshaft...

enjoy your build, keep updating as you go


AC Ward

"I will be in Afghanistan all day, week and month...."

[black75098]

will 350 engine be a simple swap for 307? will i have to change motor mounts?

[a.c.ward]

the 305 and the 350 are part of the small block gen I family... if you get an earlier than 85 (two piece rear main seal vs. one piece rear main seal), just about every external part is interchangable... intake, distributor, exhaust manifolds, valve covers, oil pan, water pump, starter, brackets for alt p/s, AC, etc are all the same...

if it is a later model 350 with one piece rear main seal, most everything listed above works, except for a few small pieces, maybe the flex plate for automatic, or flywheel for manual....

enjoy your build, take plenty of pictures, keep us updated...

a.c. ward

"I will be in Afghanistan all day, week and month..."