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WARNING: DO NOT use my method - below.

I tested it and my boost gauge showed 14psi, and climbing. My foot was only half way down, and revs had only reached about 4500. Wouldve kept climbing if i didnt back off.

Hope i didnt F*CK anything. Any thoughts on that ?

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ok, here's what i did.

strip a wire long enough to feed through the male clip and around into the contact point.

you can feed the wire in thru the back of the clip, exiting as seen in the pics.

clip it back together, ground the new wire , or run it thru a switch first, and the mod is done.

totally reversable, no cutting, and not very detectable if you use a subtle colour like black.

see pics coz my explanation sucks.

post-29392-1153993670.jpg

post-29392-1153993701.jpg

Edited by Munkyb0y

Just a word of warning. I tried the high boost mod, but hooked it up without breaking the existing circuit.

-Explained in my previous post above-

Ummmm, dont do it this way.

I hope i didnt F*CK anything. Any thoughts or advice on that ?

To me that doesn't make sense. As i understand it the solenoid is pretty much either open closed. It closes to keep boost at stock 5psi before 4500rpm, then after that the ecu grounds the negative side, completing the circuit and opening solenoid valve to increase boost to 7psi (bleeds an extra 2psi through)

So by grounding the negative side (whether you sever the actual wire or not) the solenoid should stay open, to keep a constant 7psi. All that will happen with the wire still connected but a constant earth also connected is that above 4500rpm the ecu will ground the solenoid via a second point, making zero difference to boost or the solenoids state.

More likely theres something wrong with your wastegate or solenoid valve. Does boost stay smooth and sit at its proper position without this mod done??

Although if someone knows i'm totally wrong please tell me cause i'd like to understand how this is happening.

yes, holds boost fine normally.

right after this happened, i pulled over, ripped the wire out, back to standard, and it was holding 5 - 6 psi then up to 7 - 8 psi after 4500rpm. always has been fine.

the thing that got me was that it produced very little boost at the time of the 14psi episode.

i'm sure the thing would have wound out to 20psi if i throttled it and didnt pull back.

afterwards, i was a little concerned with the health of the turbo.

i started the car hours later, cold, idling at 1100rpm or whatever cold start is, and gave it a decent rev.

had a look at my exhaust and saw some white/grey smoke.

could this be seals? or just rich cold start ?

no sign of smoke when i got home.

white/grey smoke on cold start. doesnt last long, a few revs later it's gone.

is this a sign of a problem ?

i wouldn't think so mate. If it only reached 1 bar it should be fine. A lot of people run there's at 14psi and although it will shorten the turbo life, one boost spike up to that shouldn't really affect it at all. Still wanna know how the f**k this can occur though, i'm stumped

Hmmmm, one thought actually mate. The way you have done it might give you a fairly dodgy earth. Just because it looks like you have just fed it through into the clip and it might not be making a good contact. This could possibly cause the solenoid to open and close sporadically and cause compressor surge. This is a stretch but i can't for the life of me figure out any other reason for it.

If you were to strip back some of the wire and solder the new ground directly on it to make sure you get a really good earth it might work fine then

i cant explain it either.

u see the pics above, that's exactly how it was hooked up.

i used the stock airbox hole to bolt down my earth.

what if it jumped to 20psi? i was trying to watch the road at the time, but i'm sure i caught it at its peak, around 14-15psi.

tell me once more i havent f*cked anything, and the smoke is standard behaviour for a 3" exhaust on cold start. coz i need reassurance to move on from this :D

i guess if there is something, it will show itself soon enough.

I'm gonna take it for a bit of a caning today and make sure all is holding up.

Hmmmm, the solenoid acts as a bleed valve. ie it lets air escape through the vacuum line as to delay the wastegate opening. The ECU will open it or shut it, as previously stated. Chances are u actually shorted the terminals and the ECU couldn't open or close it and it was in a constant open state. Hence preventing the wastegate opening, hence causing a constant raise in boost. IMO only

Edited by schultzr33
i cant explain it either.

u see the pics above, that's exactly how it was hooked up.

i used the stock airbox hole to bolt down my earth.

what if it jumped to 20psi? i was trying to watch the road at the time, but i'm sure i caught it at its peak, around 14-15psi.

tell me once more i havent f*cked anything, and the smoke is standard behaviour for a 3" exhaust on cold start. coz i need reassurance to move on from this :happy:

i guess if there is something, it will show itself soon enough.

I'm gonna take it for a bit of a caning today and make sure all is holding up.

This is normal behaviour, mine does it as well...Hope this helps

Hmmmm, the solenoid acts as a bleed valve. ie it lets air escape through the vacuum line as to delay the wastegate opening. The ECU will open it or shut it, as previously stated. Chances are u actually shorted the terminals and the ECU couldn't open or close it and it was in a constant open state. Hence preventing the wastegate opening, hence causing a constant raise in boost. IMO only

Hmm in that case you would definitely have blown a fuse somewhere. But the problem being that with the solenoid not opening at all (As if he had shorted the supply and stopped the solenoid getting any voltage) the valve should stay in its shut state, ie only letting turbo achieve 5psi of boost. You would almost have to have a leak somewhere that was letting a shitload of air bypass the wastegate, thus stopping it being pushed open to regulate the boost pressure.

All in all very odd. Especially that its now working fine...

Hmm in that case you would definitely have blown a fuse somewhere. But the problem being that with the solenoid not opening at all (As if he had shorted the supply and stopped the solenoid getting any voltage) the valve should stay in its shut state, ie only letting turbo achieve 5psi of boost. You would almost have to have a leak somewhere that was letting a shitload of air bypass the wastegate, thus stopping it being pushed open to regulate the boost pressure.

All in all very odd. Especially that its now working fine...

it worked fine on standard ecu boost before and after, i cant explain what happened there, except that it caught me totally off guard. as i said earlier, it seemed to make very little power at the time, as if free spooling, which got me paranoid.

i wonder, has anyone else tried this boost mod without actually breaking the circuit of the black grounding wire?

i dont pretend to fully understand the workings of the solenoid and harness involved. but perhaps this plays an integral part in it all.

Hope all turns out well. I used a bleed valve with the standard dual stage solenoid in my R33, works well if u wanna go a simple cheap dual boost setup...

PS... ur car would look hotter with clear indicators

cheers man. all seems ok. i'm assuming the smoke on start up is nothing, just rich/cold start or something.

clear indicators huh? are you giving some away ? :P

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