sbmopar318 Well-Known Member Joined Jan 29, 2007 Messages 226 Reaction score 69 Location Illinois Apr 30, 2009 #1 what octane should i run in a 10.25:- 1 compression 440ci? 93 octane been ok?
Demon416 A-Body Joined Feb 3, 2009 Messages 2,357 Reaction score 124 Location WI. Apr 30, 2009 #2 I run 10.75.1 compression on 93. That should be OK, if your engine has hardened valve seats.
