Ok i hooked a MBC up ti my stock twins on the 1JZ and no matter what direction or setting the controller is at i get boost cut... It will spool really fast to about 15psi and then bog down at WOT!!!

The way i hooked it up is waste gate to waste gate then compressor to compressor as if it was a single turbo set up...

Any ideas to fix my problem???

Setup:
3" Y-Pipe and Down Pipe
Fat IC
2.5 hardpipes
HKS BOV
thats it...

Come on ANYBODY???

How much boost were you making before installing the MBC with that setup? Just curious!

I'm not sure I understand how you hooked up your MBC ... to take you literally, you are missing somethings... Just directly connecting your wastegates won't work, and without boost cut, you'd run them easily past 25psi and run your motor lean...

Typically, for the 1JZ, you take hoses from each wastegate, and hook them together with a tee, same for the vacuum source. Then normally you'd take a hose, and connect the tee'd off wastegates to the tee'd off vacuum source. The hose that connects the wastegate tees to the vacuum tee, is where you want your bleeder valve located. The idea is, you want the bleeder valve to bleed off vacuum pressure to the wastegates evenly.

It just sounds like your vacuum lines are not correct, because if you close your bleeder valve all the way, closing it off, and you are still hitting boost cut, something isn't hooked up right.

Yeah i have it hooked up exactly as you described and i know it isn't the vacuum line because if i just join the two connections after the tees (where to mbc goes) it's back to stock!!!

So today i hooked up my buddy's bran new turbosmart mbc and the same thing happens at any setting!!!
The problem occurs when ever i hook up a boost controller... The connections are teed and everything works as stock..

Any suggestions???

ok so if you removed just the MBC, and hook up just regular hoses to the wastegates, how much boost does the car make with that intercooler and exhaust setup?

9~10psi...

Something isn't right then, because if your lines are right, when you put maximum tension on the MBC boost controller valve spring, it should act as stock, with stock psi pressure.

The idea with a ball/spring MBC is that the less tension you have on the valve, the more vacuum it will bleed off, thus building more boost.

The symptom you are describing suggest that you are bleed off too much vacuum with the MBC hooked up for 'some' unknown reason.

Keep in mind, that with the stock 1JZ injectors, and stock MAP sensor, you should be hitting boost/fuel cut at 1 bar (14.7psi). You should be able to run boost right up to that with no problem though!

Good luck.