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Old 12-21-2015, 12:01 AM   #1
jacklegjim
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Join Date: Aug 2011
Location: Lebanon TN.
Posts: 20
Question about raising compression ratio

I built a 77 454 .030 over, 781 heads 3 angle valve job, port mached and cleaned up. Stock bottom end, 870 street avenger carb.
Lunati 60203 cam. The pistons have a 10 cc dome and heads and block have been milled to true up. I have not driven the truck it is not road ready yet but, I have ran it a lot. After thinking about it I should have went with the
30cc dome Pistons because I don't even think I have the recommended
Minimum compression ratio for the cam I am using.
I built the motor a few years ago and I have no idea what I was thinking when I went with the 10cc pistons.
My question is would it be worth it to put a set of the 30cc dome
Pistons in. I could do for less than $500 and it would be a lot easier
To do it before I put the front sheet metal on. I don't detect any issues with it now just wondering if it would be a substantial power increase with higher compression ratio.
Thanks Jim
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Old 12-21-2015, 11:39 AM   #2
steveo3318
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Join Date: Apr 2014
Location: Sumrall, MS
Posts: 381
Re: Question about raising compression ratio

Just change the heads. Go down to a smaller cc in the heads and get some aluminum ones while you are there. It will wake it up. It will cost a little more but you won't have to pull the engine. Jmo
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