Boost range on a turbo xs MBC

[cjridert1]

Ive never used a mbc and my buddy is having fits with his (just put it on). They are 1psi/turn correct? 12 is the max amount he said he could get out of it - are there different springs in these or is it progressively different? Thanks in advance!

 

[knochgoon24]

I don't think any MBC is 1psi per turn. Does he have a boost gauge installed? And he should have no problem getting 12psi out of it. He must have it hooked up wrong or something is wrong with the MBC.

 

[selmerguy]

What is the wastegate spring pressure?? That is what matters. Generally you can run 1.5x the the wastegate spring pressure. The MBC should not matter much.

 

[SR20drag]

What is the wastegate spring pressure?? That is what matters. Generally you can run 1.5x the the wastegate spring pressure. The MBC should not matter much.

This is true. I've gotten as much as 2x the wastgate spring pressure on my internally gated GT2871R with the same MBC but you will get some creep and it won't hold much past 2x. AS for 1psi per turn on the turbo XS MBC that is wrong. You should turn it all the way down and then back it off 2 full turns and you should be very close to the WG pressure. From there you can back it off 1 full turn and then test your pressure. From my experience it doesn't change much at first and then progresses rapidly after that. Be careful when you get past about 25% over your WG pressure. I wouldn't turn it more than a half turn until you reach the desired pressure.

 

[cjridert1]

We got it - Turns out he was a bit confused apparently. However, he did show me page with turbo xs saying that 1 turn = 1 psi? Thanks guys!