I just had it happen to me and I'm wondering what I can do to combat it.

I just installed my 3" catback and 2.5" downpipe. I have a small exhaust leak also that will be fixed shortly.

Here's the scenario:

I took it out after installing it to see if everything would be ok. Well I hit the gas and I boosted to 15psi. Then out of the blue it started rising to 19psi!! It scared the hell out of me. I proceeded to turn my boost down to 10 psi but it still creeps up to about 14-15.

Is there a fix for this or what? I know there were threads before but I don't have the old boards website anymore. Please help.

Thank you
Erik D

Might be time for a better flowing O2 housing (ported EVO III or 2G, stainless steel)

PLEASE READ THE FORUM RULES
What turbo are you running? Stock internal gate?

Only fixes are bigger flapper and turbo porting or smaller exhaust...

Sorry Mike.

Stock turbo with stock O2 housing. I think I will go to a ported housing and see what that does.

Thanks for the info (and the tolerance of a Tech section newbie).

I agree with the both of them. Order a 34mm flapper from TRE (as I did) and pay Raptor to install and port your turbo. You will also want to upgrade to a better o2 housing or have yours ported. I always had boost creep in cold weather. I upped to a o2 housing with a dump and it didn't help. Then, I had raptor put in the 34mm flapper and port the turbo. Now it is all gone.

How much did you get the flapper for?

You may want to check and see first if Elite carries them, otherwise I bought one from Slowboyracing for $28 if I remember correctly. TRE is the other place that sells them as mentioned before for I believe the same price or close to it.

i had nasty creep for awhile. i ended up porting a 2g o2 housing and removing the divider between the wastgate outlet and turbine outlet on the o2 housing. this helped greatly, but didn't fix it. i then ripped off the turbo ported the turbine inlet spent most time on the area going into the wastegate hole ( taking out the sharp bend and making a smoother transition) as well as slightly enlarging the hole itself. doing that along with removing the step in the exh. mani. and port matching it all togethar killed the creep. took some time, but well worth it. this was on a 14b in a 2g with the stock wastgate flapper and 3in dp w/ no cat.

as stated above, you need to find a way to promote gas flow through the wastegate hole since you promoted flow through the exhaust wheel (hince causing it to spin harder/faster, which made it overrun the wastegate acutator).
AKA either restrict the exhaust, or port/hog/upgrade other stuff.
good luck.

Eric, I am probably Porting CVD's and upgrading his flapper this weekend if you are around, you can probably come see the finished product. I can call you when I am done if you are interested.

That would be awesome!!! I want to see what I'd have to do. Right now I just keep my foot off of the floor until I can get the fix done.

that too :idea:

You don't actually need to put on a bigger flapper if you port it correctly. Running a bigger flapped means that you cannot run as high of boost. I had my 16g ported so that there was no creep with a 3" turbo back exhaust. The big trick is where to do the porting at.

I have had no boost problems on my 16g at 20psi. I guess I have only had it tuned for 20psi for a couple days until DR. Rick decided to work his tuning magic.
:censored:

While this is true in part in certain instances, it is not true across the board. Contouring the wastegate entry can help in some cases, but not all. The wastegate hole diameter becomes a bottle neck in many systems with increased exhaust flow. You can make the entry into the wastegate as free and easy a transition as can be, if the wastegate itself is too small it is still a restriction and will still cause boost creep. Larger flappers have been a consitant and proven method of controlling boost creep for many years and not without reason. As far as not being able to run higher boost, depends on the porting going into the flapper area and the diameter of the hole, it can be made too large for the diameter of the flapper and hense cause blow open at higher boost levels. The entry into the wastegate can be over-ported and also cause an issue with premature opening of the flapper, as well as causing an unnecesary turbulant path to the exhaust wheel itself. For a 34MM flapper, a wastegate hole of 28-29MM and a properly ported housing will most of the time control boost creep without causing issue with blow open or negative effects on flow to the exhaust wheel.

Personally I would only run an internal gate on smaller turbos (up to a 20G). They may work for larger turbos, but IMO, if you are going for that kind of performance, why settle for an internal gate.

Cause going external costs to much :)

Cause going external costs to much :) [/b][/quote]
If you want to play, sometimes you have to pay. DSMers as a group are very resourceful and that is a good thing as far as getting a lot of performance for as little money as possible in general. I do personally believe though that there is a level where people try to save money in the wrong areas and skimp on things that really should be done right. IMO this is one of those things. If you are going large and are putting the money down for the big setup, it really isn't that much more initially to do it right and go with an external gate. It is all about how serious you are about what you are after and what you are willing to do to get it.

I like Mo's quote at elite. I think it is something like this, "If you want to play hard, you have to pay hard." BTW, an external isn't that expensive. my brother, 92tsiawd84, has an external tial 38mm sitting here. It cost around $250 shipped. If getting a bigger turbo, it costs $75-$100 for an internal WG and it still may creep. An external is $150 more and is less likely to creep. I would rather spend the extra money because it will be safer. Just my opinion though.

I don't care too much for external because most of us already have larger exhausts and that's loud enough. You add the external and it's unbearable (IMO).

Eric, you are thinking of atmospheric dump. You can run an external gate without dumping it to atmosphere.

Oh, OK. I didn't realize that. Thanks.

Some of those tubular O2 housings with the internal dumps are even worse than an external because the internals start opening very early while an external doesn't open until you hit full boost.

You have to remember that restriction in a tube is consistent with the length of the tube. A wastegate port is only a restriction for 1/2", so it is not that big of a restriction. The low pressure area created on the other side will help to suck the exhaust out of the wastegate hole. Just think of the stock TB on the high HP cars, they get away with it because it is not very long.

Anyway, after taking my turbo off and porting it 3 different times, I finally figured out how to eliminate the creep on my 16g. I had a full 3" from the turbo back, so that is a good boost creep test.

I have heard O2 dumps make the car much louder, but on my brothers car, it didn't seem to be that much louder. It just seemes to have more of an air whooshing noise. IMO

You have to remember that restriction in a tube is consistent with the length of the tube. A wastegate port is only a restriction for 1/2", so it is not that big of a restriction. The low pressure area created on the other side will help to suck the exhaust out of the wastegate hole. Just think of the stock TB on the high HP cars, they get away with it because it is not very long.

Anyway, after taking my turbo off and porting it 3 different times, I finally figured out how to eliminate the creep on my 16g. I had a full 3" from the turbo back, so that is a good boost creep test. [/b][/quote]
So by that theory then, it wouldn't hurt to run a smaller turbo gasket that protruded into the exhaust flow by a centimeter or so because it is only .030" thick or so and couldn't be much of a restriction. Or weld a washer in your exhaust pipe and not worry because it isn't very thick. Also, if diameter of the gate doesn't matter, maybe people are wasting money going larger internal or external. I agree to some extent with your comment about the restriction being somewhat length dependant as well, but only in certain applications within specific velocity ranges. The higher the velocity of flow, the less it will require to create a significant restriction. Would you agree with that?

Yes, I would agree with that. It also depends on the size of the opening on the other side. The larger the opening the bigger the pressure differential will be. On the outlet side of the internal gate has a very large area it gets dumped into, so it will have a large low pressure area. Because of that it will help to suck the air through the opening for the wastegate.

It would flow better if you opened it up, that is for sure. You should be able to get it to flow sufficiently without going to a larger flapper. That was my point. It would just help to prevent it blowing open at higher boost.

I agree with that also, there is a point that just porting will solve creep issues. I have seen some sad attempts at porting to remove creep that actually hurt the flow of the turbine housing. In smaller cases where it is done correctly, that should not be a problem.