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Hi all,

There's a wealth of info in the rb30 thread - but it would be nice to have a thread about what pistons everyone's used - CR, head gasket used for CR, forged or not, brand, pin heights etc etc.

I saw one guy in the rb30 hybrid upgrade dyno results thread is using 10:1 pistons on a turbo rb30.

Please post away your piston specs - I'm in the process of doing up a rb30 so would appreciate any input!

Cheers

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I have 8.3:1 CR, Stock pistons, OEM RB26 Head gasket

How is it off boost?

Aries Pistons, probably can go better but never had a problem and made massive power..

CP's - look on Ebay US, they're cheap as!

CP's - look on Ebay US, they're cheap as!

Hi there,

Just was checking out Ebay US but couldn't find CP's for Rb30's - do you have a link?

Cheers

I only found the MAHLE RB30 pistons

MAHLE RB30DET

Also these cheap Rods...

Rods

Seems very cheap...just over $1k delivered for forged bottom end parts (how strong thats another question...assuming its at least better then a standard rebuild).

Would those rods suit those pistons ?

Edited by KISIN
good i think? bit hard to say cause i dont have anything to compare too apart from the 25 which this motor eats for breakfast off boost!

how would you expect it to feel?

Hard to say on the net, sluggish i guess is the closest word

....havent been on the forum for long so sorry if this has been covered a billion times.

But when doing the 25/6 head swap on the 30 bottom end doesnt it lower the compression a fair bit due to chamber size (i think i read that sumwhere).

Anyways, how much does it lower it, say if you have 9.5:1 CR with a rb30et, wat would comp be if you just did the str8 up 25 head swap and didnt touch the bottom end?

Thanks

Jon

Edited by VKYOOT

we just got a new set of mahle 40 thou oversize forged pistons from hi octane. They look very schmick!

Will be the first set of pistons used in one of the many rb30 builds weve done that hasnt come from CP.

Judging by the specs on the piston box i imagine it will net a comp ratio of about 8.2:1, same as the flat tops CP provide for the conversion.

Edited by r33_racer
....havent been on the forum for long so sorry if this has been covered a billion times.

But when doing the 25/6 head swap on the 30 bottom end doesnt it lower the compression a fair bit due to chamber size (i think i read that sumwhere).

Anyways, how much does it lower it, say if you have 9.5:1 CR with a rb30et, wat would comp be if you just did the str8 up 25 head swap and didnt touch the bottom end?

Thanks

Jon

About 8.8 at a guess

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