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Idea about eliminating boost creep

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fr33b1rth

20+ Year Contributor
280
3
Jan 20, 2003
Kalamazoo, Michigan
Correct me if'm i'm wrong, but boost creep is caused by the wastegate not being able to flow enough air to bypass the exhaust turbine. The reason why people use external dumps is because it enables the excess exhaust gas to be extremely efficiently re-routed via the wastegate.

A stock O2 housing simply dumps the wasegate gasses into the exhaust causing violent turbulance in the O2 housing because it is interfearing with the exhaust gasses coming from the turbine. This reduces the ability of the exhaust gasses to flow out of both the turbo and the wastegate.

From what i understand, lots of people either can't use an external dump because of state laws, or simply don't like being extra loud.

I have yet to see someone take an external dump, and route the wastegate dump via another mild steel tube further down the exhaust, say right before the cataletic converter and merging it with their existing exhaust at an angle that is almost paralell to the exhaust. This would still allow for very efficient exhaust gas flow for both the turbine, and the wastegate, thus reducing boost creep almost just as much as just the external dump.

The most efficient exhaust is one that has these features:
1. Low restriction
2. No sharp bends, thus smooth flow
3. Some kind of heat shielding, such as exhaust wrap, or similar coatings.
4. Nothing that creating turbulance in the exhaust.

Has anyone tried this, or are they going to?
 
1stGenRocks said:
yes, thats been done. its called a rerouted external dump.

I know that it's been done, but i meant around here. I see people complaining about boost creep and everyone telling them to get an external dump. I don't think too many people know about this though.

Who knows, i could be wrong and everyone any their mother could be doing it :p
 
There was an old company that made DP's just like that years ago. They would have the WG dump right before the flex section of the DP. This would help with scavanging but I doubt it will fix boost creep. Most of the time it isnt that the O2 housing is to big, it is that the WG "hole" in the turbo is to small. I have seen a number of people throw an external dump on to try and fix it and it doesnt work. The only real way to solve it is to get port wokr done on the exhaust housing and make the flow of the WG passage as efficient as possible. The other option is to go with an external gate.
 
Yeah, I got rid of my creep with 5 min. of porting and an O2 dump. The porting gets rid of it all together.
 
hey put2gether how bad was your boost creep... Mine goes from 18 psi where the MBC is set and creeps to 30 in a few seconds.. I'm thinking i will go with an O2 dump... I wasn't sure if you had in like that or something smaller..
 
i have wicked boost creep. Ive been told its cause of my "3 downpipe on a stock 14b.
is this true?
i also have a problem with a Slowboy boost controller. (Ive installed it all ways Screwed all the way in and out and switched around the lines) When it is Installed i just loose all control over boost and my autometer boost Gage is pegged a 20psi Gage out after turbo spools up.it climbs slowly like normal at first then spikes Wide open.

If i bypass the the boost controller and plug it back into the waste gate actuator.
i stay firm at 10psi and creep to about 15psi to 17psi under load

Is the boost controller broken? Ive checked to make sure the spring and ball were not
stuck or something.
 
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