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Rb20 Wastegate On Rb25

040122

By 040122,
in Engines & Forced Induction

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040122 Collaborator

040122

Posted
Posted

hi i tried searching but found no usefull results.i want to know if anyone has put an rb20 wastegate on their rb25 turbo. has there been problems? was it easy/hard? is it neccessary to do other mods? currently all i have is 3inch cat back. i want to do this mod because i want my car to appear stock. thanks guys

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hardsteppa Grand Master

hardsteppa

Posted
Posted

.i want to know if anyone has put an rb20 wastegate on their rb25 turbo.

thing is though son, I know it sounds like, oh wow I'd be able to boost like, all the way up to 10 psi....but I found it made point-oh-shite all of difference and unless you get one for 10 bucks, not worth chasing down.

I would suggest the adjustable kinugawa wastegate with the low-pressure spring, that will bolt on, give more responsive boost as well as some degree of adjustable boost control. They're only $100-something off ebay new.

self_slaughter Contributor

self_slaughter

Posted
Posted

Yeah I dropped one on my neo because my actuator couldn't hold shit anymore.

As said not really worth the effort unless you score it for next to nothing.

Not gunna suddenly make the car a powerhouse over a couple of psi.

GTSBoy Grand Master

GTSBoy

Posted
Posted

ok cool ill check that out

Be aware that you can't run more than about 12 psi on a stock RB25 ECU without it cracking the shits at you. After that (actually really, after about 10 psi) you are into the need to tune/swap* ECU area already.

*swap on R33, tune (via Nistune) on R34, or swap.

GTSBoy Grand Master

GTSBoy

Posted
Posted

No.

The car will feel better with 10 psi than it will with 7 psi and a dump added.

But it's not as if it's an either-or sort of thing. A good dump pipe is almost an essential upgrade. The increased internal volume and better flow of the dump (whether drainpipe type or a good long split) will speed up the building of boost and make the car feel stronger even without adding any extra boost. And it will usually also add some extra boost on its own as well, just from reduced restriction. Given the price (a few hundred), it's pretty much a forgone conclusion that you should have one.

And naturally, you should always run any (stockish) turbo car at the highest boost you can (within the limits of the various support systems) so as to maximise benefit of having a turbo. So a boost control upgrade is also a near-compulsory thing. And it's also only a low amount of money (between $20 and $500 for your typical options).

Just do it (both).

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