Author Topic: 403 with 350 heads? (Read 1935 times)

77transamfan · « **on:** October 02, 2006, 09:25:59 PM »

I heard that you can put a set of 72 chevy 350 heads on a 403 olds and get a lot better horsepower and compression. If i put them on would i have to change anything else such as carbourators? Can i just bolt them on and go? Is it ok for the motor?

REDDEVIL · « **Reply #1 on:** October 02, 2006, 10:41:04 PM »

Actually 68-72 should work. Here's a good site for that info. The compression will go up. I'd be careful when it comes to temp since our 403's aren't known for running cool anyways. Check this site for info on the 403.
http://www.442.com/oldsfaq/ofe403.htm#E403%20403CIDEngineDetail

Tin Indians Rule · « **Reply #2 on:** October 03, 2006, 12:59:09 AM »

No expert here but I don't think you'll easily modify the OLDS 403 to accept any Chevy head!

I think the story you've heard is to get a set of OLDS 350 heads and put them on your 403. That'll make more power, compression, etc and anything after 1972 will have hardened seats for use with unleaded fuel.

REDDEVIL · « **Reply #3 on:** October 03, 2006, 10:15:36 AM »

Quote

No expert here but I don't think you'll easily modify the OLDS 403 to accept any Chevy head!

True! I read the post so fast I didn't see the word Chevy. It's the 68-72 Olds 350 heads that fit and up compression.