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How Much Boost Can Rb25's Stock Internals Take?

RxGTR

By RxGTR,
in Engines & Forced Induction

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R34GT-t_07 Enthusiast

R34GT-t_07

Posted
Posted

An R34 RB25 det neo can take 300 KWATW before the internals need to be done an R33 can take around 250-270 before the internals need changing. it all depends on the turbo ur getting some turbos can produce 220 at the rears on only 9 PSI like mine which is An r34 turbo which has been changed from busshel to ball-bering and hi-flow.

Deathwish Apprentice

Deathwish

Posted
Posted

im running a standard engine except for a race head gasket and around 1 bar on the lower map which gives me 400bhp and 1.2bar on top map which gives me 549bhp. It gets thrashed every time i use it and its absolutely cracking.

Sheng Grand Master

Sheng

Posted
Posted
An R34 RB25 det neo can take 300 KWATW before the internals need to be done an R33 can take around 250-270 before the internals need changing. it all depends on the turbo ur getting some turbos can produce 220 at the rears on only 9 PSI like mine which is An r34 turbo which has been changed from busshel to ball-bering and hi-flow.

I've seen a few R34's with over 350rwk running stock internal, don't ask me how but..

But yeah do a search dude.

Turbz RB-25 Experienced

Turbz RB-25

Posted
Posted

mate, boost has nothing to do with it (well, it does, but not like you think).

For example, you can run 14psi boost from your stock turbo pretty safely, however, if you fit a T88 turbo on your engine and run 14PSI, your engine will most likely die.

For this reason, people usually base how safe internals are based on power.

I've found that the internals of a RB25 engine are generally safe between 250-280 rwkw, providing you have a nice tune without any detonation over 50.

Cheers

l0WRB Mentor

l0WRB

Posted
Posted

couldnt have said it any better turbz lol some ppl on here offer horrible advice!

all comes down to the power your making on what boost levels, and how healthy your motor is to start with and how good your tune is.

mite last 1 day or 3yrs all depends on alot of things.

Lithium Grand Master

Lithium

Posted
Posted
mate, boost has nothing to do with it (well, it does, but not like you think).

For example, you can run 14psi boost from your stock turbo pretty safely, however, if you fit a T88 turbo on your engine and run 14PSI, your engine will most likely die.

You're right, boost isn't everything (I wouldn't say nothing by any stretch of the imagination) but I would be far more confident of running a T88 on the side of my stock engine at 1bar than a stock turbo. The T88 will have far lower turbine pressure and heat from an overworked compressor than a stock turbo and will not magically make stupid power just because a T88 is a big turbo, the big power numbers on low boost seen on some engines running T88s are partly as a result of the big cams and revs that the engine has been built to use to rev high enough to justify the bigger compressor.

Lithium Grand Master

Lithium

Posted
Posted (edited)
i wouldnt say 14psi is safe for a stock turbo though. That wont effect the internals but the turbo def wont last

Yeah it can have an effect on the engine in the relative scheme of things, the turbine housing and wheel are TINY and at that boost level the pressure and heat in there will go through the roof. That ends up with a much higher chance of reversion, and reversion raises the cylinder temperatures something crazy - high cylinder temps are what increase detonation and ultimately can speed up the wear and tear of the engine.

I partly upgraded my turbo as I wanted to go a bit quicker but was already at 10-11psi on the stocker, as far as I am concerned running >250kw @ wheels on a big turbo on 1bar is FAR nicer on the engine than running just over 200rwkw on the stock turbo on the same boost level despite the higher power level. You would be surprised at how little extra force is put on the bottom end by running a decent matched turbo on 1bar with a good tune versus the stock turbo on similar boost, if not a bit less.

Making more power on the 1bar with a decent turbo using the standard rev limit and good tune is the definition of having your cake and eating it too with an RB25DET, if you are looking for a bit more power out of your stock internals.

Just my opinion, anyway.

Edited by Lithium
R34GT-t_07 Enthusiast

R34GT-t_07

Posted
Posted
I've seen a few R34's with over 350rwk running stock internal, don't ask me how but..

But yeah do a search dude.

'

Ye thats true. 300kwatw is the safe mark this is what i was told by several tuners here in VIC how ever one of the tuners had tuned an r34 gtt to just over 340 @ the rears on stock internals.

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

Please use the search.

There was a topic on this late last week, and another about a week earlier.

Keeping info/posts to one/two threads makes the longer term better when people search and find detailed threads with lots of history/info.

You can always make a number, however how long it lasts is another question

Thanks.

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