well i'm using a homemade MBC it works great and holds 10psi solid in the non v-tec lobes but i notice that after v-tec the boost drops to 7-8psi. anyone have this experience??

its on a mini me set up, i have the timming a little more conservative up top in the 8psi range, is it possible this could be causing it?

by the way i'm running uber1.70
Tial 38
T3 48/60
MBC


any ideas are greatly apprecaited

 

what turbo are you using?

 

strait T3 48/60, 60 trim

 

I am guessing you have the same turbo as me? It's probably your shitty internal wastegate.

 

yeah... i got rid of the internal W/G for a Tial, which is dumping to atomosphere. i'm starting to think that maybe the true setting on the MBC is actually 7-8psi and creeping to 10lbs, then settling back down to 7-8lbs. I'm basicly trying to avoid having to buy a comercial MBC.

any ideas or solutions to my problem is appreciated...

 

your probably right, its creeping to 10 psi and settling back to 8 psi, and even a name brand mbc will do that, i had a turbo xs mbc on my talon and it would hit like 18 psi then at about 4800 rpm it would drop back to like 15-16 psi and hold steady there

 

is there anyway to deal with this creeping issue? i havn't been able to find anything, or do i just have to deal with it? turn it up to 12 and hope that it'll settle at 10lbs?

 

alright... i figured it out! i have a 90* silicone coupler elbow comming off my turbo, and a 2" metal "j" bend that goes from turbo to intercooler was jambed into the corner of the 90* coupler elbow and restricting flow... apparently it was trying to sqeeze 10psi of boost through a 1.5" crack i took the "j" bend and trimmed off about 2 inches at the end and reinstalled making sure that there was no restrictions... took it out and boosted up to a steady 10lbs in 1st,2nd and 3rd.

 

glad you fixed it, i was jus gonna suggest buying a 10psi spring for the ext wg...