Register now to get rid of these ads!

Hot Rods Heads to Block mismatch, do I need matched heads?

Discussion in 'The Hokey Ass Message Board' started by charlesmajor, Jun 2, 2021.

  1. charlesmajor
    Joined: Jan 15, 2010
    Posts: 27

    from tx

    I have 390 (Cadillac) that I found out today has 365 Heads. Is this mismatch a problem? I know the 390 heads would be better breathing and would help out a 365 block, but am I hurting compression and power by running the smaller heads? This is a 1957 Cadillac Limo- not doing any racing so 5HP here or there is not a deal breaker.
    Charles in Dallas

Share This Page

Register now to get rid of these ads!


Copyright © 1995-2021 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.