I want to replace my non computer controlled carbed 305 with a 1970's 350 with tbi. I want to remove the tbi and go back to carb set up I have now. Will I have any issue's with performance with just changing the manifold and dist to non ECM units. I am a newbe to the DDC and really want to stay with the old school carb set up. Will I have any issue's as far as cam or heads with the change?
Thanks for any input.

 

Keep the heads, intake and carb from the 305 and bolt them onto the 350 shortblock.

 

OK I am learning as I go, why would I want to put the heads from the 305 on the 350. I guess I left some things out, the motor (350 ) was bored to a 355 has ported and polished 882 series heads and a mild cam giving it about 300 rear wheel hp. I really don't know much more about the internals, I planed on haveing everything looked at to make sure there are no bearing problems or such.

 

882s are trash, the heads on your 305 are better.

Check what pistons the 350 has from the rebuild and calculate what compression ratio you'll come out with, though.

 

Do I need to do any thing to the heads to install them on the 350. Don't I have to go with the cam from the 305 as well. Maybe I am getting in over my head here. I already know I would have to replace the valve seals on the 305 heads. Whats wrong with the 882 heads. I guess I am trying to use as much as I can off the 350 without spending a lot more money. I shoud have done more home work I guess. Wouldn't I have to rebuild the 305 heads. How can I tell whay pistons are in the motor?

 

882's have large, poorly-designed combustion chambers. The ports don't flow very well. The castings are thin and prone to cracking. Other than that, they're okay...

If your 350 has dished pistons (a fairly likely case with 70's 350s), the smaller chambers of the 305 heads will raise compression to a more performance-friendly level. You don't have to do anything to them to install them on a 350, but most likely valve stem seals need to be changed, and it wouldn't be a bad idea to change the valve springs so you can run a better cam. Other than that, the engine really doesn't know or care what the heads are.

The best way to tell what pistons are in the 350 is to remove the heads and look at them. Posting pics would probably allow us to tell you what you have with pretty good certainty.

 

Thank you for the info, are there springs that you would recomend, I will have the motor by Sun. and will remove a head on monday and get some pics. I picked up a performer dual plain manifold and a street fire vacuum and mech advanced HEI dist.I will also be useing my Holley 650 vacuum secondary carb.When changing the heads do I get a gasket for the 350 or for the 305?

 

For the 350