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Rb25 On Boost At Idle?

hardsteppa

By hardsteppa,
in Engines & Forced Induction

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hardsteppa Grand Master

hardsteppa

Posted
Posted

So was rigging up a vacuum line to do the ol' skool steam cleaning of the engine....pulled off the boost controller hose that's connected to the bung on the std intercooler return pipe (connects to crossover pipe) and instead of it pulling air in at idle, it's pushing air out? So it's under pressure instead of under vacuum? How can that possibly be, shouldn't intake be under vacuum at idle?

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https://www.sau.com.au/forums/topic/381478-rb25-on-boost-at-idle/
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R33 Eddy Proficient

R33 Eddy

Posted
Posted

THIS

is what you are going to end up with

Really? what about WATER methanol injection... that does not cause this problem.. sure it might if heaps of water got in but a small mist couldn't hurt could it?

89CAL Grand Master

89CAL

Posted
Posted

water meth is atomsied so it works, Have seen a conrod not 2 weeks ago that looked like the one above due to water in the cylinder.

Sucking water into your engine through a vac line is a new one, and also not the smartest idea in the world.

TiTAN Grand Master

TiTAN

Posted
Posted

Really? what about WATER methanol injection... that does not cause this problem.. sure it might if heaps of water got in but a small mist couldn't hurt could it?

WMI operates at 150+psi and injects in the order of ML per minute a garden hose into a vacuum line does not operate the same way.

pipster11 Grand Master

pipster11

Posted
Posted

i think its mainly popular in the usa

i was a member of a usa subaru forum when i had my outback and a few ppl on there used to do it

ur supposed to use a thin clean line, warm the car up, raise the revs a little and dip the end of the clear line into some water and suck a little up, maybe 1-2cm's length on a 2-3mm hose

supposedly it'll vaporise a little on the way though the manifold and then turn to steam in the motor and clean the carbon out (subaru's apparently get a lot of shit in the heads/valves)

don't think i ever did it but yeah, just a little info for you guys

maybe i'll try it on my puss-bucket corolla :)

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