Which Rotor Compression?

[mlautier]

I need a new rotor for my fd engine. If i\'m not mistaken the compression for the 3rd gen rotrs are 9.0 : 1. However i found a japanese supplier that sell 9.7 compression rotor and claims that these are compatible with both the FC and Fd RX7\'s. Is this correct ? What are the effects of installing an incorrect compression rotor on the engine??

[MikeLMR]

sound like series 5 NA rotors, raising compression ratio will help off boost power, but will tend to limit what pressure you can run ultimately (excluding changing fuels etc. etc.) you\'d not be able to use just the one obviously and you then need to change the flywheel as they are a different weight to FD rotors

[sdminus]

I think high compression rotors will make tuning it a bit of a knife edge.
Like mike said it will limit the boost you can run to a point. other than that it should make  good power if you can tune it safely.

Make sure it runs on good fuel and charge temps are the best. I know of reasearch donw by a uk sports car manufacturer who increased the compression on a turbo piston engine to way above that of say a diesel engine. This was done using high levels of boost. The key to this was there charge cooling system.

IMO build it with high compression and run it on methanol as a drag/ track car.


i would stick to turbo rotors

Scott