kleach18

I am having a problem with my 90 Turbo II and boost creep. (straight 3 in exhaust will do that)

Would installing a manual boost controller and lowering the boost to as low as it will go be a temp fix for this problem untill I have the time and money to port the wastegate?

Kris

Rpeck

No, a MBC can only raise boost, not lower it. Infact the same is true for any boost controller. You need to resirict your flow for a cheap solution until you can port the WG. put on a cat, hook up the stock intake Etc.

-Robert

kleach18

But wouldn't the boost controller releive the extra pressure after what it is set for. I want to run about 10 psi, but the boost just climbs, so its not usable boost. wouldn't the mbc feel 10 psi after the wastegate opens up and after 10 PSi vent it?

Rpeck

No the boost controller just limits what the wastegate see's. You are bleeding off the boost that the wastegate see's alowing it not to open until your preset amount. However the boost that the turbine see's is not changed by the MBC, it can only be bleed off by the WG. Thus, you can only raise boost, not lower it with a MBC.

-Robert

kleach18

So if I set the mbc to 10 its not gonna let the WG see any pressure till it gets to 10 PSI. So it would go to the WG at 10 and then I would have the same problem?

Rpeck

Yup, that about sums it up ... but it might make the problem worse .. since you are trying to start bleeding it while you are already at 10 PSI .. if your wastegate cannot handle the creep now, it will most likely creep worse it it does not open until after 10, it has alot more pressure to bleed off in alot less time.

now if it starts at 6 pSI .. it has less pressure and more time to bleed the creep off.

I would not mess with a MBC at all till you port your WG, or as a temp fix, restrict your flow.

kleach18

If I had access to and lift how long do you think it would take me to take the turbo off and port the wastegate?

Rpeck

That all depends on your skill level, and how much **** is in the way. ~2 Hrs to pull a Turbo. But really to do the port job well, and make sure you only have to do it once, I would put a larger cover on the WG and port it large. But that is going to require equipment you might not have.

really, hard to say.

kleach18

Well< i'm planin on taking the turbo off myself but I have someone local here that can port it that knows what he's doing.

Thanks for all the help Rpeck!!!