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First posts so dont go too hard. This is also my first LS build..
Trying to find my dynamic compression ratio. I tried using the online calculators but im getting some high numbers. I live in Hawaii so its mostly sea level driving, 92 octane only, no e85, I do not want to use octane boosters.
The online calculators are giving me 10.7:1 STATIC / 9.8:1 DYNAMIC
LS1
PRC 225 HEADS 62CC Chambers
3.903 bore
-3.2cc pistons
3.622" Stroke
.045 head gasket
4.035 gasket bore
6.125 rods
Deck clearance: .006 out of the hole
I currently have a tsp 228R 112 lsa cam but do not have the cam card so I assumed the ABDC @ .05 to be 42*. Is that right? I will replace the cam if needed but I'd like to use it if I can. Any cam recommendations welcomed. Car will be mostly a street car with some skid racin if a track ever gets built here.
Last edited by MixdPlate; Feb 24, 2026 at 06:40 PM.