Just some pics of some parts I installed today. Made a huge difference in my boost, and I gained at least 3 psi across the board. In a turbo, thats worth 10-15whp.
My stock N75 for reference, in case I forgot how it went on. That is an "F".
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The J installed, nothing really to document there. Just that the harness went under that accordion hose instead of over. and it barely fit for me, but its not pulling too bad.
So in this pic you see how easy it is to install your MBC. I have inserted a "T-splitter" that came in my Overboost kit in 2 places. One on each hose. That is a temporary position, and learn from me. Dont tighten any clamps until EVERYTHING is hooked up. I had to loosen many times to figure out the best positioning:
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In pic 3 you see the MBC installed. Pretty basic, just make sure the hoses go to the corrct fitting, it DOES matter:
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In pic 4 you can see that I found a way to use that clamp that was included to bolt this to the firewall a bit. That stud was pre existing, so i just found a nut to fit it. In this next pic, note that I altered the hose lengths greatly as I decided on my positioning. Snipped a little bit at a time:
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Pic 5 shows the setting I guessed about. I didnt want to hurt anything, so I just turned it down a lot, less boost, and tightened my lock nut. I figured I could always open it for more boost if I had to:
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My last pic shows some hosing I used to prevent the MBC from banging on the firewall as I drove. I didnt hear it bang, but I'm sure it would have. I took an old piece of hose, and just tie wrapped it around the back:
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This stuff is fully out of the way of my cover, and my cover went on perfectly stock. It makes a HUGE difference in the cars power, but im sure ill have a few issues to deal with as I test it out some more.
i been playing with my adjustment knob you see in that last pic. Its quite frustrating, and tricky. Not cause its so sensitive, but cuz its so NON-sensitive.
That little brass square you see.. thats my Boost Control Solenoid. That opens the waste gate when it thinks boost it high enough. That boost control solenoid is made for a higher power car. So it tends to want to boost higher than my ECU likes. This throws you into limp mode, where you cant go past 10psi, or in hard limp mode, cant go past 5 psi. (which is slower than stock). Just takes turning off the car and restarting to reset that problem. So, in order to stop the spiking from the new boost solenoid, you add this MBC I added. This is a ball and spring type device, fairly simple. The more you tighten the knob, the tighter you make the spring against the ball. Thus, the more pressure it takes to push the ball up. Thus, the more you tighten the knob, the more PSI will be kept in the system before it is released. The general thought is one turn = 1 psi. But I have not found that to be true. That MBC only handles a max of 21psi, so I think i'm nearing the end of its range. I am peaking at 18-19psi and then it drops steadily to redline.
My stock N75 for reference, in case I forgot how it went on. That is an "F".
The J installed, nothing really to document there. Just that the harness went under that accordion hose instead of over. and it barely fit for me, but its not pulling too bad.
So in this pic you see how easy it is to install your MBC. I have inserted a "T-splitter" that came in my Overboost kit in 2 places. One on each hose. That is a temporary position, and learn from me. Dont tighten any clamps until EVERYTHING is hooked up. I had to loosen many times to figure out the best positioning:
In pic 3 you see the MBC installed. Pretty basic, just make sure the hoses go to the corrct fitting, it DOES matter:
In pic 4 you can see that I found a way to use that clamp that was included to bolt this to the firewall a bit. That stud was pre existing, so i just found a nut to fit it. In this next pic, note that I altered the hose lengths greatly as I decided on my positioning. Snipped a little bit at a time:
Pic 5 shows the setting I guessed about. I didnt want to hurt anything, so I just turned it down a lot, less boost, and tightened my lock nut. I figured I could always open it for more boost if I had to:
My last pic shows some hosing I used to prevent the MBC from banging on the firewall as I drove. I didnt hear it bang, but I'm sure it would have. I took an old piece of hose, and just tie wrapped it around the back:
This stuff is fully out of the way of my cover, and my cover went on perfectly stock. It makes a HUGE difference in the cars power, but im sure ill have a few issues to deal with as I test it out some more.
i been playing with my adjustment knob you see in that last pic. Its quite frustrating, and tricky. Not cause its so sensitive, but cuz its so NON-sensitive.
That little brass square you see.. thats my Boost Control Solenoid. That opens the waste gate when it thinks boost it high enough. That boost control solenoid is made for a higher power car. So it tends to want to boost higher than my ECU likes. This throws you into limp mode, where you cant go past 10psi, or in hard limp mode, cant go past 5 psi. (which is slower than stock). Just takes turning off the car and restarting to reset that problem. So, in order to stop the spiking from the new boost solenoid, you add this MBC I added. This is a ball and spring type device, fairly simple. The more you tighten the knob, the tighter you make the spring against the ball. Thus, the more pressure it takes to push the ball up. Thus, the more you tighten the knob, the more PSI will be kept in the system before it is released. The general thought is one turn = 1 psi. But I have not found that to be true. That MBC only handles a max of 21psi, so I think i'm nearing the end of its range. I am peaking at 18-19psi and then it drops steadily to redline.
