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need boost/vaccume line help fast

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Old Oct 29, 2011 | 12:04 AM
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Default need boost/vaccume line help fast

Could someone check this out real quick to make sure I wired all the lines correctly? Got a track day on sunday, and am getting it tuned tomorrow night, so just making sure everything is right before that.


The red line connects straight to the boost gauge, the yellow one goes to the BOV nipple.



Yellow line goes to the MAP



red is going to the turbo, yellow to the wastegate, and the blue is the controller/regulator.



Thanks guys
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Old Oct 29, 2011 | 01:52 AM
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Yes it looks fine. Boost/vac is boost vac. nothing special about it unless you have one way valves or some ****
Old Oct 29, 2011 | 03:32 AM
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Originally Posted by Faeflora
Yes it looks fine. Boost/vac is boost vac. nothing special about it unless you have one way valves or some ****
k thanks, that's what I was thinking.

For some reason my boost gauge isn't working. It never goes past 0PSI, it moves in the mmHg area below 0 tho. I cant seem to figure out why, all the boost gauge wiring seem to be correct. Any ideas?

Gauge is a STRI X-Line 52mm.
Old Oct 29, 2011 | 09:02 AM
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I'd recommend that you source the pressure line for your wastegate from somewhere after the IC and before the throttle. You will have pressure drop through the IC as flow increases. This will result in boost sag, even though you have a nice MBC. Joe Perez had a nice, easy to understand write-up on this.
Old Oct 29, 2011 | 10:57 AM
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Originally Posted by hornetball
I'd recommend that you source the pressure line for your wastegate from somewhere after the IC and before the throttle. You will have pressure drop through the IC as flow increases. This will result in boost sag, even though you have a nice MBC. Joe Perez had a nice, easy to understand write-up on this.
Your talking about this red line, connected to the turbo right?




I'm gonna look that up, thanks.
Old Oct 29, 2011 | 12:19 PM
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Yes, that's the one.
Old Oct 30, 2011 | 06:50 PM
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Originally Posted by hornetball
I'd recommend that you source the pressure line for your wastegate from somewhere after the IC and before the throttle. You will have pressure drop through the IC as flow increases. This will result in boost sag, even though you have a nice MBC. Joe Perez had a nice, easy to understand write-up on this.
i sourced all mine from the manifold after the tb.

you should not source boost from the compressor housing. you will get sag. red goes from housing to mbc?
Old Oct 30, 2011 | 07:13 PM
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Originally Posted by Clos561
i sourced all mine from the manifold after the tb.
you should not source boost from the compressor housing. you will get sag. red goes from housing to mbc?
Sourcing bov boost from the compressor housing is at least better than manifold however sourcing boost between the IC and the TB is the best.

During cruise your turbo will be pushing 100% as the waste gate will be closed. It kinda defeats the throttle body as every time you're not at full boost the wastegate will be closed trying to get to the set boost however you're limiting the pressure going to the engine with the throttle body so you get a big mind ****. You press the gas, more exhaust goes to the turbo to spool it, turbo spools more but wastegate stays closed. You press the gas some more now you're in boost however still at low throttle so the turbo spools more as the wastegate still stays closed. You step to wot, the turbo has already spooled and built up a lot more than your set psi so you get a spike in psi so your wastegate now opens and you're fine. Now you're turning keeping the gas even, the throttle is say 30% open at 6psi however your wastegate is now closed so your turbo is trying to get to the set psi so it spools more so you close the throttle to make up for it, then when you step on the gas after the turn and you get another spike again throwing your rear end into the wall where you crash and burn and die. Is that what you want? This is why you cant have nice things!!1!
Old Oct 30, 2011 | 07:45 PM
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ive never had spikes or any erratic boost behavior
Old Nov 1, 2011 | 12:51 AM
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Finally works guys, the line does not work for boost. i ended up teeing the line for the MAP and it works now!
Old Nov 1, 2011 | 10:40 AM
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Originally Posted by triple88a
Sourcing bov boost from the compressor housing is at least better than manifold however sourcing boost between the IC and the TB is the best.

During cruise your turbo will be pushing 100% as the waste gate will be closed. It kinda defeats the throttle body as every time you're not at full boost the wastegate will be closed trying to get to the set boost however you're limiting the pressure going to the engine with the throttle body so you get a big mind ****. You press the gas, more exhaust goes to the turbo to spool it, turbo spools more but wastegate stays closed. You press the gas some more now you're in boost however still at low throttle so the turbo spools more as the wastegate still stays closed. You step to wot, the turbo has already spooled and built up a lot more than your set psi so you get a spike in psi so your wastegate now opens and you're fine. Now you're turning keeping the gas even, the throttle is say 30% open at 6psi however your wastegate is now closed so your turbo is trying to get to the set psi so it spools more so you close the throttle to make up for it, then when you step on the gas after the turn and you get another spike again throwing your rear end into the wall where you crash and burn and die. Is that what you want? This is why you cant have nice things!!1!
This makes sense.

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Old Nov 1, 2011 | 10:46 AM
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This is why we can't have nice things!
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