Pistons For 1330

Yeh, Gavs mini Estate. He doesn't know what power its running, but the timing is very safe.

I like that. Low CR has always put me off charging

Question I am using a compression ratio calculator and when I put all measurements in there it gives me 9.56 but if I just change the bore size from 1330 to a 1293 and the rest the same the compression ratio drops to 9.35 is that right? Although I am getting a marginally more cc in bore?

Question I am using a compression ratio calculator and when I put all measurements in there it gives me 9.56 but if I just change the bore size from 1330 to a 1293 and the rest the same the compression ratio drops to 9.35 is that right? Although I am getting a marginally more cc in bore?

 

going from 1330 to 1293 is reducing the bore, so less cc (swept volume) not more

 

assuming unswept volume doesn't change, then compression ratio would drop as swept volume decreases

That's the one, I thought I remembered 150hp mentioned, I must be thinking of somthing else.

Update guys finally found a solution. so engine is getting liners and bored to 1293 and gonna fit 18cc +20 forged pmega pistons. if I get the piston flush to block deck I will get a compression ratio of about 8.46 that mean I can run abit more boost in the future if need too.