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over boosting

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Man that's vague. Could be the wastegate needs adjusting, could be your MBC is not functioning properly or not hooked up right, could be your manifold/exhaust housing/O2 housing needs porting depending on how bad you're spiking.
 
i have an o2 dump, i have no mbc. i just have the wastegate hook up straight from a boost source.
 
take the line off the source and stick an air compressor fitting into the line (one with a trigger valve). regulate low pressure, about 8lbs. see if you can actuate it manually. you are overboosting how? 20lbs on an 8lb actuator? be specific. maybe your vac line is shot.. mine split once and shot up to 30lbs in a half second when i was regulating at 20.
 
Ive done everyhting I check it with the compressor n the actuators work change the lines n nothing happen
 
You still haven't stated how high it is "overboosting". What pressures are you seeing? What kind of boost gauge do you have?

My bet is your wastegate needs ported or the actuator is malfunctioning/getting hung up.

Please be a little more comprehensive and descriptive with your posts. Details are key for anyone here to help you.
 
Is your wastegate flapper hole ported out to roughly the same size as the valve seat on your external wastegate? Which I am assuming is on the 02 housing since you call it a o2 dump.

You make sure you didn't pinch your diaphragm in the wastegate when you loaded the spring?

Load up your air compressor, set up the regulator at your wastegate spring pressure and see if it opens all the way and doesn't collapse on itself right away.
 
By your profile it looks like you are running 3" turbo back straight pipe on a 16g, are you internal or external wastegate?
If internal is it ported at all?

Stock 16g on 3" straight pipe may not be able to bleed enough exhaust to keep the boost regulated. Aka boost creep.
 
Need to port the turbine/wastegate passage. Or go external.. Search boost creep and you will find what you need.
 
nope the wastegate hole is not ported bc i thought that by dumping to atmosphere it was going to fix my problem
im suppose to be running 14psi ( stock wastegate pressure ) but I was creeping to 21 after 4k. after going with the 02 dump I only creep up to 19
 
Only so much exhaust can make it out of the stock sized hole, a good porting will help. By dumping to atmosphere you reduced a little restriction but the biggest restriction is still the non ported wastegate.
 
ok ill port it an see what happens. i just wanted to see if there was anyother thing i can do before porting
 
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