RB30DET

These pistons are designed for RB30 engines using R33 RB25 or RB26 cylinder heads. There are 2 types available.

1. A flat top piston with a compression ratio of 8.2:1

2. A domed top piston with a compression ratio of 9.0:1

If using the R34 NEO RB25DET head ( as used in the R33 project car ) the options for pistons are.

Please Note : The R34 NEO head has a smaller combustion chamber than any of the earlier R33 or R32 RB25 or RB26 engines.

1. ACL ( or similar ) RB30ET SOHC pistons. These have a listed compression ratio of 8.5:1 in the SOHC engine and with the smaller combustion chamber of the R34 NEO head the resulting compression ratio of 8.4 / 8.5:1 can be achieved.

2. If looking for a higher compression ratio. Around 9.0:1 can be achieved using the above mentioned Flat top CP 8.2:1 ( RB30 bottom end with RB25/26 head ) piston.

All final compression ratios should be verified by cc'ing all required measurements.