dieselman88

I've been having problems with my wastegate, so I order a new tial mvr 44mm and it came with a plethora of springs. I'm only wanting to run 10psi, I was going to just run a 10psi spring in the wastegate and ditch my hallman pro MBC. I thought I read somewhere that a MBC will help the turbo spool faster. Just didn't know which would be better, to just run the 10psi spring in the wastegate, or run a smaller 7psi spring and use the MBC to bring it up to 10.

Forcefed86

iTrader: (4)

The ball-and-seat style MBC will help spool time. They keep the boost pressure form reaching the gate until the set "cracking" pressure is reached. At that point the WG opens. Without it the WG valve can open slightly before the target boost is reached.

ddnspider

iTrader: (26)

X2- I noticed a difference in spool when I ran just off the wastegate line vs. with an MBC.

dieselman88

Thanks for your input guys, hallmans site says that it helps spool faster I just didn't see how. I'm going to run the 7psi spring with the mbc

Forcefed86

iTrader: (4)

Simple concept. Use a regulator and shop air and watch the valve in the WG. If you run a 10lb spring that means at 10lbs the valve should be fully open. But the WG will open slightly before 10lbs. Springs are progressive, they aren’t an on/off valve. If you have a 10lb MBC it holds all the pressure back until 10lbs. Meaning the WG stays 100% closed until the MBC pressure is met. This spools the turbo more quickly since it’s letting less exhaust bypass the turbo.

69-chvl

iTrader: (11)

But in theory, the w/g will open more abrubtly right, rather than nice and smooth - at the expense of spool. Probably why my turbo "hits" like a 2 stroke dirt bike.

Forcefed86

iTrader: (4)

Nice and smooth=slow response. You want it to slam open at your desired boost. Thats what the "gain" does on the electronic boost controllers.