rb25 to rb30

[VL32]

hey, the best thing to do if ur thinking of increasing power is to forget about an rb30. the main thing u want is the block. then u either want an rb25 head or rb26 head. this is because they are both double overhead cams, where the rb30 is single. if u place either the rb25 or rb26 head on the rb30 block u get a 40% power increase and if u have a decent exhaust and air intake its a bit more. i dnt know how much is ivolved for the rb26 head because it expensive. but the conversion to an rb25 head is very simple. its an amount of tapping it very carefully into place. and that 40% increase applies to N/A cars. so imagine the power if it was turbo.

[VL32]

hey, the best thing to do if ur thinking of increasing power is to forget about an rb30. the main thing u want is the block from a VL. then u either want an rb25 head or rb26 head. this is because they are both double overhead cams, where the rb30 is single. if u place either the rb25 or rb26 head on the rb30 block u get a 40% power increase and if u have a decent exhaust and air intake its a bit more. i dnt know how much is ivolved for the rb26 head because it expensive. but the conversion to an rb25 head is very simple. its an amount of tapping it very carefully into place. and that 40% increase applies to N/A cars. so imagine the power if it was turbo.

[Cubes]

:headspin:

[Eug]

But that being said.. If you are going to the expense of a motor build you would probably be better off building it to suit turbo or even better buying a turbo model & rip the turbo off if insurance is too high then drive it around as NA for a while until you can justify spending the $$.

I am not doing this conversion - but am quite interested in what you are saying here...

Basically what i gather is tha; build a high compression RB30DET, take off the turbo?

and drive it as an RB30DE - then its just a simple matter of bolting the turbo back on??

EDIT: I've thought about this with a mate - and just seems unpractical.

tuning, exhaust, intakes and lil bits an pieces need to be changed...

dis-regard the post // but will leave it for others.

[Eug]

*poke*

i'd like to restart any discussion on the rb30de... more specifically with the 26 head.

if anyone has done the 25/30 or 26/30 conversion care to post any dyno graphs or 1/4 mile times?

what compression do you run 10:1? 11:1? did you retain the vvt? (how do u tune with the vvt?) etc...

yes i've read ALL the pages in the forced induction section, but it doesnt cover the questions related for n/a applications.

thanks

Eug

[dontfeelcold]

10.5 with the rb25de pistons, sounds good to me.

Would forged pistons/rods be necessary when running comp that high? or should the rb30 rods and rb25de pistons be enough.

My rb30 has done 230000kms, would a basic rebuild (bearings, hone the bores and new rings on the rb25e pistons) be advised or would I get away without doing it. Or does it depend on what it all looks like inside?

Would a brake upgrade be required for the power increase? (i have a r31 silo)

[Eug]

10.5 sounds good, i'd be inclined to go to 11 if possible.

i've read that a few of the 30DET guys using stock parts so i cant see why not.

forged pistons wont be necessary, however lightweight pistons wud be good.

yes it does depend on the condition of the block.

brake upgrade would be advisable but a good set of pads and rotors may be sufficient depending on how u drive.

eug