Best Source for MBC?

sleepydsm · 11-25-2005

Whats the best place to have a MBC hooked to? Intake manifold, fuel pressure solenoid, or turbo compressor outlet?

TheBlizzard · 11-25-2005

I am pretty sure you want it as close to your wastegate as possible. Hook one line up to your BOV and the other line up to your wastegate and have the lines be as short as possible without harming them.

Thats how I have always had mine but maybe theres a better way.

tpunx99GSX · 11-25-2005

I lines going from the BOV to the Intake mani, and t'd to the wastegate, and the MBC is inline with the line thats going from the T to the wastegate. I think craig didnt remember the line for the intake mani.

sleepydsm · 11-25-2005

Right now I have the BOV and MBC hooked into one line from the intake manifold. I just want to give them each their own source. So the BOV is gonna go to the intake manifold by itself, and the mbc is gonna be right from the turbo compressor outlet to the MBC to the external WG.

CDeutsch · 11-26-2005

Quote:

Originally Posted by sleepydsm

So the BOV is gonna go to the intake manifold by itself, and the mbc is gonna be right from the turbo compressor outlet to the MBC to the external WG.

That's how I run mine. In stock form the Mitsu's I've owned have the BOV source on the engine side of the throttle body and the WG/MBC on the opposite side of the throttle body. I'm not sure if you can tell much in driveablitiy though by switching things up. The WG/MBC source on my stealth was moved to the engine side of the TB and I thought I noticed a really small difference in throttle response but I doubt I could tell by driving someone elses car how theirs was hooked up.

EDIT: On second thought maybe the boost was spiking a bit higher. I can't recall for sure. The point is the difference was really small and insignificant.

s1ngletracker · 12-24-2005

If you want the best vacuum source you should go from the intake manifold if possible.

**Kracka** · 12-24-2005

The best place is the turbo compressor outlet, that way the lines are as short as possible which helps prevent/minimize boost spike.

turbo2086 · 12-25-2005

I did have mine on the intake manifold. Now I have it coming from the turbo outlet. It will help minimize boost spike, as well prevent the turbo from over working if you have some boost leaks. I didn't notice much of a diff in drivability.

**Kracka** · 12-25-2005

Quote:

Originally Posted by turbo2086

I did have mine on the intake manifold. Now I have it coming from the turbo outlet. It will help minimize boost spike, as well prevent the turbo from over working if you have some boost leaks. I didn't notice much of a diff in drivability.

That won't change how hard the turbo works. Aslong as you have the boost gauge tapped off the intake manifold, the turbo is building the same amount of boost no matter where the MBC is (assuming you keep it set at a certain boost level).

EclipseGST · 12-25-2005

Yeah it will. Say you have the line off the intake manifold and there is a boost leak in between the turbo and manifold. The turbo has to work twice as hard to get the pressure to the WG line coming off the intake mani for the WG to open and level out the pressure. If you put the WG vacuum source on the compressor housing, it is one of the first things to see boost pressure. So there for the WG opens but you only see little boost in the manifold and on your boost gauge.

This happened to me, I could hear my WG open but I wasnt getting much power out of my car and I was only seeing 7-10psi on my gauge. What happened is my vacuum line on my BOV blew off so there was no pressure on the spring. When I would hit about 10psi on my gauge the BOV would pop open causing a boost leak, but I could also hear my external WG open seeing 15psi of boost. There for the turbo wasnt over working itself trying to compensate for the boost leak.