My old 305 was pulled out for a cam change, then I found a 350 with a bad crank that was destroyed when the motor was low on oil. The block, head, pistons, rods, etc. are good, so I thought that I would just swap out the crank from my 305 since they have the same stroke and replace bearing and rings. Question is will I have to have the motor rebalanced or not. Also, will hypereutics be lighter and offset the misbalance between the rotating and reciprocating assemblies. I dont want to pay for a balance.....will this work?

 

Rods and the crank are the same weather it's a 305 or 350. It's the beauty of the SBC everything fits everything. Oh yeah one more thing if they ran it low on oil and wiped out the crank personally I'd have the rods reconditoned or use my 305 rods.

 

This question has been asked before on this board and if remember correctly the balance of crank is different. Yes the 350 and 305 have the same stroke 3.48" but due to the different bore size I think the balance would be different.

If you want a 350 crank, I have a ZZ4 crank from a used short block I bought and made into a 383 engine for my '69. contact me if interested. I live near Cleveland, OH

 

Engine balancing issue here. Have a qualified balance/machine shop tell you if it will work. The cranks will work but they are not of the same mould. Even a machine shop that doesn't balance isn't qualified to tell you untill it's chucked up on the balancer.

 

Yes it will work, and no they are not the same. The stroke is the same between the 305 and 350 cranks, BUT the 305 crank and rods are less beefy... they are subtantially lighter than the 350 parts, but the 350 parts are alot stronger.

 

Lighter means More HP right .

Yes it will work. But I wouldn't want to use it. Just try and find a good 350 crank in a junkyard or contact Todds87IROC and get that one.

Good Luck, Garrett

 

junkyard is the way to go, that or find someone with 350s lying around...sometimes spending 150$ to buy 2 old and beat up looking complete 350s ends up being a gold mine...

 

Another place for a 350 crank is a machine shop. My local shop will hook you up with a 350 crank for about $150 thats been ground and includes main and rob bearings.

 

thanks for all the help, If I have anymore questions I will post it. Any suggestions you might want to make are greatly appreciated.