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Hi all,

I recently bought a buggered RB25 turbo and thinking of Hi-Flowing it.

I've heard mixed feelings about this from one or two people, however I'd

like an opinion from people who have done this before and have some results

to prove.

My current mods are FMIC, pod filter, Bleed Valve, BOV, 3" turbo-back exhaust.

From my own knowledge after bolting on a hi-flow I think it will be necessary to get an Apexi Power FC (or at a minimum an SAFC), probably a Z32 air flow meter and bigger fuel pump and possibly bigger injectors.

Does that sound about right?

I aim for around 250rwkw but with a reliable set up that won't go KABOOM on me.

From peoples experience, is it possible to easily obtain 250rwkw with a hi-flow RB25 turbo?

And if it can reach 250rwkw, what other mods would I need to build up to around 300rwkw?

I'm thinking about getting a HKS actuator over the standard, would this benefit in gaining the power I'm aiming for?

Thanks for your help..

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you will not be able to reach close to 250rwkw with a hi flowed standard turbo, you will need something bigger, such as a gtrs or a 2540

and yes you should get a power fc otherwise its a bit of a waste (power and petrol)

first thing you should get is a power fc

powerfc, injectors, z32, clutch, fuel pump, electronic boost controller, 3" dump, front, hiflow cat, fmic, hiflow

should get you 250rwkw on 1.3 bar. if you wanted 300rwkw then gt30 ext gate and tomei cams

I think you'll be pushing the standard high flow turbo pretty hard if your aiming for 250rwkw its doable, just how long do you want the turbo to last is the question. Definitely need to tune a/f ratios and timing aswell.

300rwkw (400hp) is alot of power for a standard RB25DET, so after youve done all the support systems ie fuel system, computer,suspension etc youll have to get the internals done $$$$$$$$$$$$$$. Which isnt cheap. Then you might want to upgrade those brakes.

I reckon aim for around 220rwkw with the highflow and the pfc, this should be safe and reliable.

Just my opinion ;)

I have seen all the reviews on the forum about the hiflows being great and people getting 250rwkw + but every tuner i have spoken to has told me to stay clear of them if i wanted any more than about 220rwkw... i guess it depends on who you listen to at the end of the day.

I was really keen to go for a standard hiflow but have decided to go HKS from what i have been told.

i would agree with LANFOH that around 220rwkw would be around the mark.

Blade, what sort of power have you got from yours and what other mods?

Gcg stage1

straight through, no cat

fmic

pump

z32

550 injectors

cams

ebc

powerfc

i clocked without injectors and z32afm at around 13-14psi 200rwkw

and now with injectors and afm its running around 18 psi with 248rwkw on a tight arse dyno, the engine is knocking a bit in diff temps might have to fix up timing etc.

this arvo in 3rd gear at 6800rpm it knocked to about 81 which isnt too good.

People seem to quote pretty massive power figures on here, for example an RB20 pulling 200rwkws on its standard turbo, with a fmic and thats more or less it... even though you run out of spark after 13ish psi..... I've got a hi flow and all the usual backup stuff, and have just managed 200kws out of it....

But the hiflow has great response, and seems to get along great.. RB25 would crack with one I'd reakon...

People seem to quote pretty massive power figures on here, for example an RB20 pulling 200rwkws on its standard turbo, with a fmic and thats more or less it... even though you run out of spark after 13ish psi.....  I've got a hi flow and all the usual backup stuff, and have just managed 200kws out of it....  

But the hiflow has great response, and seems to get along great.. RB25 would crack with one I'd reakon...

mine hasnt cracked and it wont hopefully crack. however i cant go any higher cause its at its maximum potential

I guess he means the exhaust wheel due to excess heat from the mount of air being compressed. Sydneykid has a few cars with rb25 hiflows and gets 250rwkw with tomei cams and they drive the cars all the time. A hks 2540 would be a waste of money, its a proven mismatch and makes excess lag. Pick of the bunch for rb25det is hiflow should get around 220rwkw without cams or 250rwkw with cams and good tune or hks gt-rs should do 260rwkw without cams (im pretty sure).

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