i just installed my Hallman Pro RX MBC this morning. installation was pretty easy. i just had to remove my Injen pipe/intake and i had enough room to work with. before i installed the MBC i was boosting about 17 psi. i know evo's push around 19 psi stock so i assume i have a minor boost leak which i plan on checking once i replace my FMIC next week. when i installed the MBC it was turned all the way off and i was only boosting 11-12 psi. i turned the knob like 8 times and i boosted 15-16 psi so i knew the mbc was installed correctly. when i got home i switched the light spring to the heavy spring and turned the boost up to 18 psi. i guess my overall question is "is it okay for me to turn the boost up to 18-19 psi even if i have a slight boost leak?" technically my boost would actually be 20-21 psi if i didnt have my boost leak.

 

let me know if any of you guys need help with the install.

 

fix the boost leak, crank boost to 21psi...

 

you'll be fine, as long as when that leak is fixed you dont peg 30 lol, i had a friend once on his gsx had greddy profec B boost controller and he had a boost leak for queit awhile and he keep turning it up and up and up, well one day i decided to help him fix his leak so yadda yadda 2 hours later we found that a coupler was wore out changed it, went for a test run and he pegged atmospheric pressure because he had messed up the profec B and the solenoid got stuck open LMAO ............ Boom

 

N/M... see you remembered to change the spring

 

Yeah mine didnt come with another springs...............

 

mine is sitting to come to me
when do u need to change the spring menaing, should i change it before installing it?
will be checking u when i install mine

 

hallman is one of the best MBC out there, peroid.

 

i changed my spring after my hallman mbc was already installed. i didnt realize that i would only be boosting 11-12 psi with the mbc turned off. it says that the lighter spring is good for increasing up to 5 psi and the heavier spring is used to increase a lot more.

 

how did you run the MBC off the bov or what?

 

This may sound stupid, but check to see if your gauge is leaking. I had many instances where I would only boost 14psi, but the car didn't feel any "weaker". Turns out the vaccum line into the intake manifold kept getting a hole in it...

Could very possibly be a boost leak, but just be sure to check EVERYTHING!

 

couple things, if you have a boost leak, you'll run richer than needed, so yes, it "should" be safe. If you're only boosting 11-12#'s with it turned all the way down, maybe your gauge is off? It should be 14#'s. And the fact that you were only recording 17#'s when stock boost is closer to 19#'s also points to your gauge reading lower than it should.

 

when do u switch out the springs on the hallman??
mine came with an extra heavier spring

i plan on boosting 21 psi on the stock 8 turbo

 

Take out the spring with it installed, make sure to watch out for the ball, it will pop out first chance it gets!

 

Which spring is better for a close to stock Evo?