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I desperately need some help regarding the differences. I suppose the questions i need answered are:

1) What compression ratio does the RB20DE have...i know the RB20DET is 8.5:1

2) Do they make the extra compression using piston size , combustion chamber volume or a bit of both?

3) What are the casting numbers on each head....going from memory my old head was 74L4, the new head thats now on the car is 72L3 (?) The numbers are different and i cant remember exact designations. Do all RB20DET heads use the same casting number?

Basically new head on car and its meant to be an RB20DET head, but cranking pressure is 225psi and the car pings under load, forget about boost :rofl: Just trying to confirm i have the right head..

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hi roy the rb20 de had a conpression of 10.5 to 1 not sure on the actuall design of them but I seem to remeber some one saying the heads were a bit differnet.

but then again I have heard of several rb20 de's being turbo charged with out too many issues

sux about your head I would be looking into it. I still have my old head sitting in the garage even if you jsut wantto take measure ments

cheers

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220-225psi is spot on 10.5:1 comp.

:( TD06 and 10.5:1 compression. :Bang:

Why are the easy things always so hard :Oops: I cant even get the right head, can someone have a quic read of the casting no. on their DET ( exhaust side around cylinder no.2) and post what the no is and also the year model GTST

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