Hi Guys,

My car has been going into limp mode at 20psi and I thought there was a leak somewhere after I installed my boost gauge, but after all the great help and some googling I figured I am probably overboosting because of the chip and perhaps there is something wrong with the N75 valve.

However I did find a simple solution for the overboost and that is to install a MBC to limit the max boost to below 20psi so my car will not go into limp mode.

I found a set of install directions ( http://www.boostvalve.com/overboost.html ) and plan on using a cheap forge MBC I found on ECStunning. Sorry for all these newbie questions, never done this before.

1) The forge unit has 3 paths does it mean I can just not use one of the T valves?
2) How do I adjust it?
3) Should I just get a better MBC and not use the N75? advantages? disadvantages?

-Randy

 

please for the love of god do not use the forge mbc, it is a pos! Please get a real mbc, even the boostvalve will be fine when running in their overboost mode.

 

Ok, then what would you do to correct the problem?

 

i run a turboxs mbc. The hpbc works very well for me w/o the n75. A basic mbc (not the forge) will work fine in the boostvalve overboost mode.

 

will the turbo spool up faster with the Turboxs if I bypass the N75?

 

a little and it will hold boost longer

 

humm I did some research on boost controllers and I found that the Hallmans are pretty good too.

Whats the difference between the HALLMAN EVOLUTION RX KIT (http://www.hallmanboostcontroller.com/applic.html)

and the Turboxs HPBC ? what does the bleedvalve on the turboxs do? Aren't all MBC bleedvalve types?

 

They are, but on the HPBC one adjustment controls the wastegate boost while the other adjusts bleed, which is how and how fast boost is leaked (or "bled"). The Hallman is only boost, so you could get boost spike or erratice action, whereas with a "boost/bleed" type (TurboXS) it will feel smoother and deliver power more effectively

 

The hallman is a good ball and spring mbc and the turboxs hpbc has both ball/spring and a bleed valve.

No, mbc are either bleed/gated or ball and spring. The bleeds constantly bleed off boost pressure as it lets some reach the wastegate. The ball and spring is a set psi (so to speak) and all the pressure is held back from the wastegate until the pressure is high enough to push the ball back and make its way to the wastegate. This induces faster spool ups and far less smoother boost onset. Meant for real size turbos, not Vag stock ones

 

I think I am having the same problem after installing my N75 valve. I am getting like a hesitation and I pull into full boost and my check engine light flashed at me for about 7 seconds and the car seemed to be in limp mode. Is that actually limp mode? Would resetting the ECU fix the problem? Cuz the car seems really powerful when it doesnt go into limp mode and I really like the feeling. What should I do? I have an unlocked APR program where I can adjust the boost with the vtune program. Should I skip the N75 valve and turn up that to have a little more boost, or keep the valve and try to turn it down to see if that helps?