Will the crank pulleys from older (pre-86) motors bolt up to the balancer on the new motors, namely an 88 305?

 

Yes

 

to add to this, i was putting my dampener on last night and the bolt is to big for the crank. this bolt was on my 72 350 before. is there two sizes for a crank bolt or something?

 

No. They are all 7/16"-20 (fine) when they leave the factory, except for certain steel-crank 283s before about 65 which had no bolt at all. Unless of course, somebody has re-tapped it or something, which is probably what had happened to your 72 model motor.

 

well the thing is is that the old crank and bolt were off the 72. i went to put the bolt on my new 383 and it was to big and wouldnt even start at all, hence why i say to big.

 

Sounds like somebody sodomized the 72 motor (probably tried to turn the motor by hand with the bolt), and drilled the hole out, and stuck some wrong bolt in it.

There is only one size for a SBC crank damper bolt. That's why you can go to the store and just buy one from ARP or Moroso or Spectre or whoever, and there's only one part #.

 

well the crank was new andi put it in myself. so i am really confused here.

 

I personally am unwilling to accept responsibility for what may have happened to your crank. I have heard of people drilling them out and using a BBC bolt, which is ½"; but of course, like I said, they didn't come from GM that way.

http://store.summitracing.com/partdetail.asp?part=10064

http://store.summitracing.com/partdetail.asp?part=16909

 

alright thank you. i will buy one on my way home now. i hope it works. i spose its worth a shot since i need one anyway.