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The time has come to start buying bits for my rb30, however, i am stuck on what pistons to get. i'm not going for excessive amounts of power, between 240 - 260rwkw is what im aiming for. reading the rb30 thread some seem to think forging a 30 for this kind of power is excessive, and i'm wondering if the money could be better spent elsewhere. has anybody put new factory pistons in ? or does anyone know of any aftermarket cast piston kits? thoughts/experience?

thanks!

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The time has come to start buying bits for my rb30, however, i am stuck on what pistons to get. i'm not going for excessive amounts of power, between 240 - 260rwkw is what im aiming for. reading the rb30 thread some seem to think forging a 30 for this kind of power is excessive, and i'm wondering if the money could be better spent elsewhere. has anybody put new factory pistons in ? or does anyone know of any aftermarket cast piston kits? thoughts/experience?

thanks!

Had a factory rebuilt engine with factory clearances and pistons up to around 300rwkw. However it busted a ring land about 2months later with a batch of bad fuel. I would think that 240-260rwkw would be fine as long as your not choking up the exh side with a small turbo.

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Had a factory rebuilt engine with factory clearances and pistons up to around 300rwkw. However it busted a ring land about 2months later with a batch of bad fuel. I would think that 240-260rwkw would be fine as long as your not choking up the exh side with a small turbo.

ah gutted thats how i lost my last engine!! did you rebuild with forged pistons then? out of interest how does a small turbo effect a big engine? does it affect cylinder scavenging and build up ex gas ?

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small turbos on larger capacity engines can choke up the exhaust side, causing excessive back pressure in the manifold, which in turn keeps cylinder temps higher the normal via the back travel of heat. On the plus side you would have awesome response, but it would more then likely be prone to detonation, especially if the tuning isnt too good.

so yeh, its messes with scavenging and creates a flow restriction which is the last thing you want in a turbocharged engine.

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