Hellos guys, I have a Evo 4 (JDM) with Evo 8 Ecu. The car has Evo 9 turbo, external wastegate (Tiall 38mm), turbo header and turbosmart MBC. The Ecu has reflash too....

I have problem with boost leak, and two days ago, I changed the BOV graddy RS to original BOV (plastic BOV Evo 4). the car run perfectly, but I put the boost controller closed, but the turbo charged 15 psi, sometimes until 19 psi with the turbo smart MBC closed....

Yesterday I changed the BOV plastic with the new Greddy RS recirc and made the same... This is normal (15 psi) with the MBC closed???

 

no clue what your question is....

But if the MBC is "closed" (no boost signal getting to wastegate), the turbo will just build boost uncontrollably. If the MBC is "open" (ALL of the boost signal going to the wastegate), it will run on wastegate spring pressure. My setup will build about 13 psi on wastegate pressure.

 

In the worst case my car should give 9 psi of boost of external wastegate, or not???

 

im more newb than you. what's mbc?

 

Correct me if I'm wrong..usually if you turn the mbc all the way to the left meaning closed you should be boosting what whatever your Wastegate is..something like that

Mbc is manual boost control

 

thanks, that definitely cleared up some confusion.