rx slim

I have a Profec B spec II, it was installed a while ago by Pettit. I have never been able to stop my boost from creeping way past 12, and when I really get onto it in 3rd gear, I can't go through my full rpm's without the rear rotor getting fuel cut to it (I read that is a protection feature). It's really frustrating to not be able to get the "goody" out of my car. I'm about to undertake a big job on the car, and bought an intercooler, radiator, vacuum hoses, and a greddy RS BOV. So I'm going to have the car apart. Is there something I can check that my be causing my boost creep? I can set my boost controller just about all the way down, and it still does it. Any suggestions?

DaveW

What mods have you done to your exhaust system?

If you have an open (no cats or restrictors) exhaust, your WG will be unable to flow enough to control boost. That is the definition of boost creep. You may have to port your WG.

dgeesaman

iTrader: (7)

Boost controllers control the movement the wastegate valve. At max boost, the controllers hold the wastegate fully open.

Boost creep is caused by the wastegate valve physically being too small. That explains why no boost controller setting will solve the problem. When you install that intercooler, expect the problem to get worse. You need to port the wastegate or change to a slightly more restrictive exhaust (e.g. high-flow main cat).

Davee

rx slim

I do have a high flow exhaust. I did wonder if the new intercooler would make it worse, okay. . .so the next step. How do I port my wastegate??? Or should I buy an aftermarket one and install it when I'm going to be elbow deep in work? Any suggestions on a good aftermarket one, or is the stock one easy to port. Thanks for your help guys

Montego

iTrader: (1)

^^+1 on what dgeesaman said.

Do a search on porting the wastegate. I remember a thread where a member did a write up.

JyRO

iTrader: (3)

rx slim - A much cheaper and easier way is to put restriction in the exhaust. Its much simpler, less expensive, faster, and safer than porting your wastegate.

Will you loose power? Compared to your current condition I'd say you will wind up with more power, because you can run full throttle at top rpm, and not get too lean and not hit fuel cut. Remember, you're going to loose power going excessively lean, and likely cause some engine damage from heat sooner or later.

I have these restrictors designed, and have built a few. If I weren't stuck dealing with the cooling system of my car, I would finalize the design, but as they are, they work just fine.

If you are interested, I could still hook you up with some (not free though). PM me if interested. And by "some" I mean, I would provide you with 3, and you can use the one that works the best. I can change mine out in 10 minutes. The hardest part is accessing the underside of the car (I have to jack mine up).

- JyRO

rynberg

When you say you have a "hi-flow" exhaust, does that mean you are running a full exhaust -- downpipe, midpipe, and cat-back? If not, something is wrong with your EBC install or your wastegate isn't connected. If so, you will need to either port the wastegate or add a restrictor plate as described above.

rx slim

Yup, there is nothing but a big steep pipe for my exhaust. I will probably take you up on a restrictor, at least to try it out, I can always go back and try to port this thing. I've also got an e-mail into Pettit to see what they would charge me to port it, and maybe adapt the flapper to a larger port. I'm sure they've done it before. Thanks for all you input guys, I was always a little hazy of the way the whole set-up worked, but this thread really helped the light bulb come on.

dgeesaman

iTrader: (7)

Hmm, well, you could search for "How to port wastegate" and see what you find.