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Discussion Starter #1
Does anyone know what the maximum safe compression ratio on a stock bottom end running pump (93/94) gas is? I'm planning on having a FR head installed later this year/early next and I was initially thinking 10.6:1, but if its possible to go higher on pump gas I'll definitely do that.

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The bigger the cam you run will allow you to run a little lower octane rather if you rased the comprssion and left the stock cams in. I bet you could get away with around 10.5 with at least stage 2 - 3 crower.
 

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Discussion Starter #3
Yeah, that's my plan, 10.6:1 with Crower 2's. I was just curious if something in the neighborhood of 11:1 is possible with stock pistons and connecting rods.
 

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11.1 seems like a lot....but I don't have any proof to back up my thoughts. I'm sure someone will chime in soon...
 

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2focusedracing
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sorry to "tag along" on this thread but same question with crower 2's & crappy 91 oct., my cyl. head is getting surfaced by next weekend. I was thinking between 10:1--to 10.5:1, any thoughts on what would be safe.
 
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