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basically if i was to buy a turbo that will actually keep up with the rb25s hunger for air would 14 psi be too much? i would of course buy a haltech, malpassi etc... i just dont want to buy stuff if at the end my engine just falls apart.

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1 bar will be fine, stock engine will handle it. Just get some kind of ecu management and you'll be fine. I'm runnng just over a bar on mine at the moment without a problem, i also have plans to go higher :( Don't worry about an adjustable fpr, waste of money IMO. What turbo are you looking at getting?

Josh,

Do you think adjustable FPR is a waste of time? Im trying to weigh up if I should chuck a bigger turbo on my stag..... Prob would just get a high flow for ease of instalment and dont have to worry about defect... Ive got all the supportive mods (FMIC, Turbo back, SITC, SAFC, EBC Splitfires ect ect...)

What else would I need to run the bigger turbo at say 14ish psi? Fuel pump? Injectors?

Josh,

Do you think adjustable FPR is a waste of time? Im trying to weigh up if I should chuck a bigger turbo on my stag..... Prob would just get a high flow for ease of instalment and dont have to worry about defect... Ive got all the supportive mods (FMIC, Turbo back, SITC, SAFC, EBC Splitfires ect ect...)

What else would I need to run the bigger turbo at say 14ish psi? Fuel pump? Injectors?

Yes get an upgrade fuel pump. Only reason to get an adjustable fpr is to push more fuel through your injectors than normal. For not much more money you can get a set of 480cc (or 550) injectors - a better idea in my view. Apart from a better turbo a quality professional tune is the key to max power.

Chris, as kiwi said, definitely get a new fuel pump, purely for the fact that the one you have now could be up to ~15 years old. fuel pump failure will cause lean mixtures and could potentially kill your engine.

adjustable FPR's can be used to allow you to get that little bit extra out of the stock injectors. the way i see it, why waste your time stuffing around with one running higher fuel pressures in a dodge attempt to save a little extra coin, just to find out that you are going to have to upgrade the injectors at a latter date anyway. adjustable FPR's have there place with aftermarket fuel rail setups that don't accommodate one, and then just use it to set the recommended base fuel pressure.

the only mods i'd add to your list would be, a decent fuel pump, and a better kind of engine management that the SAFC/SITC combo (all depending on the hiflows specs, you may get away with it). in the back of my mind would be injectors and AFM, but i'd wait to see how close to maxing them out i was first.

Ok so shopping list, feel free to make corrections and fill holes -

Management - nistune

turbo - ???

injectors - ???

Fuel pump - bosch 040

thanks for any info

what power level are you aiming for steven?

a couple of options could be, the GT3076 seems to be a favourite among RB25 owners. not too laggy and good top end result. but will require a different dump pipe, and oil/water lines, intake pipe. if your not after big power the smaller GTRS is a good responsive turbo and i believe they come in a bolt on kit that bolts up to the stock dump pipe pattern.

after you work out what power level your aiming for you can then size your injectors, if you need them. if you do 500-600cc is a good size to look at. you should go over to the forced induction section of the forum and start going through the RB25 dyno results thread and look at other peoples setups and the results they got.

I don't have a power figure I'm chasing. Just want a reliable 1bar. If I can get it to out run an aurion I will be happy. But it's more of a me being stuck in my old ways. My celica I set up to run 1 bar and it was just a nice number. ATM I just over the boost cut on cold nights. If possible I wanted to keep my stock outlet location on the turbo and still use my jjr dump.

just get a nistune board installed and tuned for 11-12psi on the stock turbo and you wont be far off that. stock injectors and afm will be fine. see how that feels and if you still want more then do the turbo.

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