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Old 08-26-2007, 10:06 PM   #17
68C15
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Join Date: Jan 2004
Location: next to my reloading bench
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Re: Compression ratios for cheap gas...

Quote:
Originally Posted by 72hotrod View Post
Cam specs play a part in octane requirements with a given compression ratio. If you're stuck with 9.5:1 you can get a little leeway with cam selection. Some of the real tech guys can explain dynamic vs static compression better than I could. Call a cam company with what you need to do and they can help suggest the right cam specs.
this is a VERY important factor. back in 98 I built a 355 with 0.125 domes under 72CC heads (882's shaved a bit) and 14* initial with 36 total (no vacuum). it ran great with 89 octane due to the cam bleeding off dynamic compression until it hit the 2300 RPM mark.

CROWER HAS THEIR S!!T TOGETHER !! (grind # 00210)
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