rb25/30 conversion

[jokerpfl]

hi guys im new to the 4x4 scene but absolutely love it. just need some advice on a conversion im doing..?
i have a gq swb patrol and i am doing a rb30 block with rb25 head and cam conversion. the block and heads getting machined bored and balanced atm with forged pistons on its way. my question is what kind of turbo would you recommend with this setup???

[nissannewby]

That's a very open question mate.

What sort of power are you looking at?
What sort of boost are you wanting to run?
Intercooled?
What is the vehicle going to be used for?

There are many options available for the RB series motors. Also maybe a skyline or VL commodore based forum could be a lot of help also.

[jokerpfl]

sorry im still new to it all but im looking at making about 300 hp and i just want to tear up the dirt and climb up dunes but also be able to smoke it up on road...

is this possible???

[jokerpfl]

yeah i want to run intercooled, external waste gate, i already have the front plenum intake

[04OFF]

Sounds like it will be fun if you can get it all done.



Why did you decide on doing a 25 head conversion ?, a RB30 single cam would do everything you want it to do !

You are fitting aftermarket pistons, and your fitting a machined 25 head, have you worked out what compression ratio you will end up with ?

With your forward plenum, is it to suit a XF Throttle body or standard (or other) and are you going aftermarket ECU ?.

And are you talking 300hp @ flywheel or tyres, and are you using a auto or manual gearbox ?


What is your budget ?




Im afarid choosing a Turbo is not always that simple ,if you want the right Turbo, there are a thousand questions that need to be answered first, can you talk to the engineer about these things , perhaps he can explain things and help you to get what you want/need rather than us "guessing" ?

[Alitis007]

Most of these RB28 hybrids ( 30 block / 25 head ) run T3/T4 in VL's. When i was doing a turbo conversion on my vl i had the option of having that combo, just the standard rb25 head with a small port and polish on the rb30 block with 30 thou oversize pistons was a 800 hp combo with the correct cams ( sorry can't remember which cams i was recommended to get) . You could also run a T04z but it will be a little bit laggier than the T3/T4.

[04OFF]

Cool !, sounds like he just needs a T3/T4 then, and he will have easy 800hp !

[jokerpfl]

someone actually recommended using a garret gtx 3076 is that bigger than the t3/t4 i think im still gonna be using stock cams from the rb25

[jokerpfl]

i think my mechanic said he was waiting for all the porting and that to be done by engineer and getting all the compression ratio and all that from him first but i am impatient lol and wanted to get turbo and all that ready so when the block and that comes back its ready to be put together.

but also a guy from c-red in perth said that any more than 300 hp and i prob be blowin gearboxes and stuff but he said at 300 i will have a fun reliable every day car... any different views on this would be much appreciated??

[jokerpfl]

plus would also like anyones opinion on an aftermarket computer to use toooo im such a newb so sorry if these questions are a bit how should i put it "dumb questions" its prob common knowledge for most of you all lol...