12 :1 compression safe for 91octane?
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12:1 is perfectly fine! It's all about DCR, not static compression. Valve events brotha, open the intake valve earlier and longer, and you'll be fine. I'm running 12:1 in my 434, w/ a 235/251 114 cam, and we were still able to throw 30* of timing at it w/o detonation. Now, on 91, you'll want to back off the timing, but you'll be fine.
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Well that is true if he backs off the timing, but then you have to ask yourself is it really worth all that. I mean if I was putting all the time, effort, and money into a nice motor with 12:1 compression the last thing i'd want to do is limit the timing just so I could run 91 octane. That's just my opinion of course...
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Well that is true if he backs off the timing, but then you have to ask yourself is it really worth all that. I mean if I was putting all the time, effort, and money into a nice motor with 12:1 compression the last thing i'd want to do is limit the timing just so I could run 91 octane. That's just my opinion of course...
12:1 is perfectly fine! It's all about DCR, not static compression. Valve events brotha, open the intake valve earlier and longer, and you'll be fine. I'm running 12:1 in my 434, w/ a 235/251 114 cam, and we were still able to throw 30* of timing at it w/o detonation. Now, on 91, you'll want to back off the timing, but you'll be fine.
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#8
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Then youre not doing what you initially asked about. If it is going to be a track car then it would probably be fine just putting 100 in there and running it that way. If this is a daily, you need to seriously consider your fuel choices. If youre going to be spraying the house down, go a point lower on compression and get a standalone with race gas.
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