I've had an MBC on my car for close to a year but recently installed 8:5:1 pistons and Crower rods after breaking a piston. Since it was fresh I wanted to really take it easy breaking it in, so I adjusted the bar/rod on the wastegate (HRC Stage II) to 2psi. I wanted to be able to almost cut boost when I have the MBC turned "off". Well now its broken in, but even when I open the MBC all the way up the boost stays at 2psi. The weird thing is, even though the boost never increased, the car was more responsive with the MBC opened. I'm going to re-adjust the bar on the wastegate to 5psi as soon as I can leave the car sit long enough to cool down. Im just baffled why the MBC did nothing.

You know to INCREASE boot, you turn the MBC all the way in, right?

Also, I don't know what effect messing with the wasetgate would have on your boost adjustability. Personally, I wouldn't leave that unscrewed while trying to set boost with a MBC. Too many unknowns there. Furthermore, the MBC's function and effectiveness is based upon building up pressure(and releasing the excess) within that whole wastegate to vacuum line hosing.

One more thing, I tee'ed off the MBC at the vacuum line from the intake plenum to the BOV. That seems to be the popular location amongst many turbo peeps. You could also do it at the compressor to wastegate vacuum line.

Jason
98' Eagle Talon ESi-T
Mitsu Super 16g Turbo(HRC)/Custom FMIC


http://springfielddsm.homestead.com/JasonsPics.html

_____________________________________
Jason ESi-T

04' BMW 325Ci
91' Nissan 240SX
98' Eagle Talon ESi (sold)

http://members.home.net/xtatdsm



if u have ball and spring MBC, then u will need to screw it in to get more boost. if u have bleeder type MBC then u will need to unscrew it out to get more boost. also make sure you don't have any major boost leaks.


Adel