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Too Many T's?

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jordan99GS

10+ Year Contributor
37
4
Jul 27, 2010
Indiana
Hey guys, I just picked up my first turbo'd dsm on monday. woot woot. The problem is that it was pre modded and swapped so things are in weird places and I'm not sure whats where exactly. My question for you is are there too many T's running off of the same vacuum line? My buddy claims that it will "spool better and boost faster" if the same line wasnt branched off of so many times. Which makes SOME sense, but this is my first turbo'd car so I'm not exactly an expert...at all. Here's what it's looking like as of now.

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The main line that runs from the BOV to the intake manifold is T'd off of 2 times. one runs to the manual boost controler which also runs to the wastegate. and the other runs to the speed density thingy. there is one untapped vacuum line that goes from the bronze-ish thing on the fuel rail to the intake manifold, but I think I'm going to T off of that for my boost gauge..

TL;DR
Is this too many T's for one vacuum line? and does this effect how my car boosts? and if so, how can i clean it up a bit. thanks in advance.
 
Yeah you definitely don't want to have anything tee'd off of the BOV line, let alone the boost controller. Try to run a single line to the BOV from the underside of the intake manifold (where it appears that line originates from), and try to find somewhere as close as possible to the compressor outlet to run a single line for the MBC. Some turbos or intercooler piping will have a nipple on the compressor housing itself, or on a j-pipe if applicable. As far the speed density goes, I have no idea where you would want to run that from, not very familiar with speed density myself.
 
OMG what a mess! I would say yes. The BOV should have it's own interference free line. Looks like the MBC is T'd in with the BOV as well. The BEST spot for that is from the WG, to the turbo nipple (if it has one), or the inter cooler pipe.
 
Holy Hell!

Wastegate needs a dedicated source line, closer to the boost source (turbo) the better. Do not have anything tapped into it.
BOV needs a dedicated source line which is un tapped by anything else. There should be a nipple on the front of the IM for it.

Fuel pressure regulator can be tapped for a boost gauge, brake booster could be tapped as well. Leave the PCV alone.

Follow this diagram minus the wastegate being tapped into the BOV.
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Where is the coolant overflow line going? That should be going to the overflow tank with liquid in it.

Is there a GM MAF + translator installed somewhere or are you running speed density? You shouldn't' be venting your BOV without either one of them.

Sorry, but that thing looks like a mess. I'd be concerned about what else is hacked up improperly. Get more pictures of the bay.
 
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Thanks for the quick replies guys, I just wanted some second opinions before I started pulling things and routing them differently. I guess the Speed Density thing eliminates the need for a maf through the use of DSM/ECM link so thats why thats there, but where should I branch that to/or give it it's own dedicated line.
 
The MAP sensor ideally should be as close to the intake manifold as possible with as short of a line as possible with no tees. If you happen to have a threaded sensor like the AEM unit, the best placement would be directly attached to the manifold by drilling and tapping it.
 
I really hope I didnt mess up by getting this car... It's a six bolt swap and the random purple wires is the radiator fan relay that he ran wires out of because they're slim fans. so thats just kind of chillin' because I ran them to a dedicated switch. There is some things everywhere and I'm going to try and clean it up a bit, or as much as possible. and now I'm kind of freaking out because its not starting...
 
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