MBC off of Brake Booster?

T

Toolfreak387

Member
:
2002 P5
I searched but couldnt find anything about it. Can you run a MBC off of the brake booster? I have a Greddy Type-s running off of the Brake Booster now. I was thinking of getting a vac block and putting both the MBC and the BOV on there. Also, what is the best way to hook up a MBC to the brake booster?
 
I'll agree with everybody and say no. The line from the MBC needs to be as short as possible. Just add the MBC in the line to the actuator and you'll be good. Remenmber set it at it's lowest setting and go from there. I ran one for over a year at above 8psi and now with all the mods I've done I'm there without one. Good luck. By the way, which MBC do you have?
 
You can definitely do it. The brake booster line is a vacuum/boost source the same as any other. I have a vacuum ditribution block coming off my brake booster line feeding my bov, boost guage, wastegate, and AFC. But I also agree that it is best to keep the route short as possible as it should lessen boost spike.

If you do tap into the brake booster line, there is an inline check valve that you must be sure to tap the line before that. If not, then your wastegate will never see positive pressure, and your motor go pop. The check valve is inside the line so you can't see it besides a slight bulge, or a hard spot you can feel by squeezing the line.

If you have the stock intercooler, there is a capped off nipple on it. This spot should work well for a wastegate/MBC boost source.

With any wastegate related mod, just be cautious with the throttle when you first test it, and keep a close eye on the boost gauge as you do. Just in case something is not hooked up right, you should be able to tell before the boost gets out of hand and something bad happens.
 
Last edited:
peepsalot said:
With any wastegate related mod, just be cautious with the throttle when you first test it, and keep a close eye on the boost gauge as you do. Just in case something is not hooked up right, you should be able to tell before the boost gets out of hand and something bad happens.
Click to expand...
You can tap into any vacuum source that sees positive pressure when in boost, which means basically any vacuum source on the MSP.

It would be easiest to just tap into the line as suggested in the how-to forum. I followed them, but had an issue. I set the MBC so I could blow freely through it and installed it following the directions, but when I tested it my boost went past 10psi and I let off because I was nervous. Any suggestions on what could be the problem?
 
livelyjay said:
You can tap into any vacuum source that sees positive pressure when in boost, which means basically any vacuum source on the MSP.

It would be easiest to just tap into the line as suggested in the how-to forum. I followed them, but had an issue. I set the MBC so I could blow freely through it and installed it following the directions, but when I tested it my boost went past 10psi and I let off because I was nervous. Any suggestions on what could be the problem?
Click to expand...

You want to be able to just barely blow through it. You want it to be really hard to blow through it.
 
livelyjay said:
You can tap into any vacuum source that sees positive pressure when in boost, which means basically any vacuum source on the MSP.
Click to expand...
Right, just as long as that vacuum source is not after a check valve. There are two check valves that I'm aware of: one in the brake booster line, and one for the vacuum chamber that feeds the VICS/VTCS solenoids. Stay away from those and you should be golden. I don't know what how-to you are referring to or what lineyou tapped, but maybe this was the problem?
 
Rawyzf said:
You want to be able to just barely blow through it. You want it to be really hard to blow through it.
Click to expand...
Wouldn't having it easy to blow through be just like not having a boost controller there at all? I was just going to try and leave it at a stock level, then gradually increase it till I got 9psi. I'll try it again when I'm actually not going out of town for a weekend. Oh wait, I won't have my car for two weeks since it'll be in the repair shop :(
 
peepsalot said:
Right, just as long as that vacuum source is not after a check valve. There are two check valves that I'm aware of: one in the brake booster line, and one for the vacuum chamber that feeds the VICS/VTCS solenoids. Stay away from those and you should be golden. I don't know what how-to you are referring to or what lineyou tapped, but maybe this was the problem?
Click to expand...
There is a how-to on installing the JoeP MBC. I followed it exactly and couldn't get it to work correctly, but maybe I needed to tighten down the MBC before putting it in.
 
orng1 said:
I'll agree with everybody and say no. The line from the MBC needs to be as short as possible. Just add the MBC in the line to the actuator and you'll be good. Remenmber set it at it's lowest setting and go from there. I ran one for over a year at above 8psi and now with all the mods I've done I'm there without one. Good luck. By the way, which MBC do you have?
Click to expand...

I am planning on getting a boostsciences dsmbc.
If i use the actuator line will it be easy to take it off again if i need to?
 
Last edited:
I installed my greddy type-s to the passenger side of the check valve. Would this be the same for the vac block? Standing in the front of the car looking at the engine i tapped into the brake booster to the left of the check valve.

peepsalot said:
You can definitely do it. The brake booster line is a vacuum/boost source the same as any other. I have a vacuum ditribution block coming off my brake booster line feeding my bov, boost guage, wastegate, and AFC. But I also agree that it is best to keep the route short as possible as it should lessen boost spike.

If you do tap into the brake booster line, there is an inline check valve that you must be sure to tap the line before that. If not, then your wastegate will never see positive pressure, and your motor go pop. The check valve is inside the line so you can't see it besides a slight bulge, or a hard spot you can feel by squeezing the line.

If you have the stock intercooler, there is a capped off nipple on it. This spot should work well for a wastegate/MBC boost source.

With any wastegate related mod, just be cautious with the throttle when you first test it, and keep a close eye on the boost gauge as you do. Just in case something is not hooked up right, you should be able to tell before the boost gets out of hand and something bad happens.
Click to expand...
 
Toolfreak387 said:
I installed my greddy type-s to the passenger side of the check valve. Would this be the same for the vac block? Standing in the front of the car looking at the engine i tapped into the brake booster to the left of the check valve.
Click to expand...
Yeah that spot is fine.
 
Please log in or register to reply here.

Similar threads

M
Rear brakes seizing up
Replies
4
Views
3K
JaredB83-MSP
J
B
Problems after brake booster replacment
Replies
2
Views
2K
Klatte
K
D
2007~2015 CX-9 Replacement brake booster - Beware
Replies
3
Views
5K
delucat2
D

Latest posts

Back