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Discussion Starter #1
im very confused i have done the trick of switching my 2 stage boost off by grounding the earth wire from the boost solnoid and its great but ive just fitted a fmic and removed the wire and put it back in place once the fmic was fitted but i now get 2 stage boost.
now this is the bit i cant work out as if you cut the wire and earth it you get high boost and if you cut the wire and not earth it you get low boost but unless that wire is reconnected to the soilnoid side then it cant get 2 stage boost and mine is earthed so how am i getting 2 stage???????
ive re earthed it loads of times and still 2 stage boost.:confused: :confused: :confused:
 

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Discussion Starter #3
i thought that but it hit 5 psi before 5000rpm and 8psi after just like 2 stage boost.
 

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Discussion Starter #4
whats the best way to check for boost leaks as the fan makes alot of moving air around that area?
 

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it could be the pressure drop from fitting the front mount.

mine also does this since i have fitted my FMIC, there is a lot more area to fill now you have the FMIC
 

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Discussion Starter #7
right i thought i sorted this out.i changed the pipe which comes off the intercooler pipe with a smarco hose.the standard one had a restrictor in which when i put the standard hose on stoped it but after driving it today i boost 8 psi(0.65 bar) then once over 5000rpm it now boost 10/11 psi(0.8 bar)
now i must have a boost leak but how do i find it?
sorry for another long thread.
 

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Discussion Starter #9
i think this would work and i was going to use some stuff i use for plumbing but wouldnt the car have to be on boost otherwise if there was a air leak off boost the it would suck it in not blow bubbles?
i still think its strange that is comes in 2 stage boost and 2 stage boost cant work on my setup.
 

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If you have a leak on boost its darn tiny hehe. I agree with hongkongphooey its quite simply the larger volume of the FMIC thats making the car feel like it has a 2stage state again. I was gonna get one myself but I'm gonna roll with an uprated R34 gtt intercooler which go straight in place of the original one :)

have you checked all the fmic pipework and made sure its nice and tight (sorry If I sound like a member of blue peter here man) as the slightest leak will cause pressure drop :/

I did this 1stage mod too and before I got it mapped with RBmotorsports Rod suggested they fit a Trust turbo downpipe ...that made all the difference man - I see about 0.8 to 0.9bar of boost (slightly different restrictor too) but it comes on thi-ck n fast since that downpipe went under there.. however I still see a slight laggyness in the sense its about 0.7bar then works its way up to 0.85ish as I get up the rev range... this kinda makes sense as you cant expect the turbo to give you all the boost off the lowest amount of exhaust air running through it :)

just some thoughts mate hope you get sorted :)
 

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Discussion Starter #11
its 2 stage boost as it will not take untill 5000rpm to get another 2psi and its hitting the 0.65 boost at 2200rpm and 0.8bar at 5000rpm just the same as two stage boost.
 

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Discussion Starter #14
right now i have changed the standard pipe i cut up and put the alloy pipe sent with the fmic and have fitted a nipple in the smarco hose and now it just boosts it hit 12 PSI before i shat myself and backed off.what is going on
 

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Hi,

I’m pretty certain I have this on mine, when I first bough the car I asked the question about removing the 2 stage boost.

Kindly enough I got the replies I wanted and set about doing this but found someone had put an aftermarket hks actuator on it and bypassed the solenoid.

Now the thing is it does exactly what you have described i.e. 2 stage boost from the same sort of rev range.

I have a large blitz fmic so I wouldn’t mind finding out whether it is the lag or if it’s something else, I put it down to the lag but I don’t know now.
 

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Discussion Starter #16
its not lag as it boost fine and then raises 2 psi so it wouldnt take 3000rpm to raise 2 more psi and now it boosts 12++++++++psi from 2500 rpm.ive got standard actulator and it ran one stage 8psi allday before i put in the fmic.
 

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Discussion Starter #17
ok i found out that one of the pipe was twisted and i have disabled the 2 stage boost so i should get 5 psi through out the rev range and it hold prefect untill 5000rpm and then i goes up to 8psi.
so if i earth the boost soilinod i get 8psi and then 10/11 psi and if i dont earth it i get 5 psi and the 8/9psi so im ethier spiking above 5000rpm or changing this on my boost soilinod is just running +or- 2/3 psi in the two stages.
 

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pitbull said:
ok i found out that one of the pipe was twisted and i have disabled the 2 stage boost so i should get 5 psi through out the rev range and it hold prefect untill 5000rpm and then i goes up to 8psi.
so if i earth the boost soilinod i get 8psi and then 10/11 psi and if i dont earth it i get 5 psi and the 8/9psi so im ethier spiking above 5000rpm or changing this on my boost soilinod is just running +or- 2/3 psi in the two stages.
I thought if you earth the soleniod you get .8 bar 11psi (ish) all the way from 2 & 1/2k rpm :confused:
 

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Discussion Starter #19
no you get 8psi 0.65 from 2200rpm but you have a hks actulator so that will be set at 0.8 bar hence why you get that not 8psi.
 

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pitbull said:
no you get 8psi 0.65 from 2200rpm but you have a hks actulator so that will be set at 0.8 bar hence why you get that not 8psi.
ahh ok, i dont think its set to .8 bar as the stock tubby gauge only reaches about 4 what is the standard boost gauge read in psi or bar??
 
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