Joined: Sat Nov 15 2008, 08:27PM
Location: NE Pennsylvania
Posts: 428
My apologies - I just reread your posts where you mentioned octane and I understand now that when you said 90 and 93 "AON" you were referring to current "American" octane numbers. Back in the 1960s and early '70s, most regular fuel V8s had between 8.5:1 - 9.5:1 compression ratios and premium fuel engines were 10.0:1 and up. Since regular fuel in the US during that time was about 94 RON (89 - 90 on current US pumps), you may be fine running the current 95 RON German fuel with a CR of 9.2 - 9.5:1. If you go with more advanced "aggressive" timing (adjusted further before top dead center) or even more compression then additional octane may be needed.