dump tube/boost question

[moonstation2000]

I have a big 16g with an external dump. Problem is, i can hear the dump opening at 12 psi even though i max out at around 19-20 psi by redline. Shouldn't my dump tube stay shut until i hit max boost?

 

[scottr126]

Yah mine does the same thing, i also have a big16g set at about 20 lbs and at low boost i can hear it opening. I still get to 20 lbs but i hear it dump early. Why?

 

[Blk_99gst]

Same here, big16g with dump tube set at 20psi. I can hear exhaust coming from the wastegate at part throttle or 10psi.

In a perfect world, yes the wastegate would stay shut until you hit your desired psi (say 20) and then open, and you wouldn't get any over shoot or anything. But since it's not a perfect world, I guess the wastegate starts creaping open anticipating your set 20psi; so you hear it, but it's not fully open yet. This isn't ideal, since that exhaust gas escaping could rather be used to spool up faster or reach your desired psi setting quicker.

Some say that an electronic boost controller would fix this problem, but I don't buy it.

 

[moonstation2000]

any known fixes? stiffer boost controller spring? different wastegate actuator? anyone have any ideas?

 

[Blk_99gst]

any known fixes? stiffer boost controller spring? different wastegate actuator? anyone have any ideas?

external wastegate, maybe.

 

[L2RTSiAWD]

You could try an FP upgraded actuator. It comes with a stiff 17lb spring.

Besides with an internal gate it will always open a little early

 

[Black95TSIawd]

or you can use a different MBC.

 

[TurBoGs-T]

or you can use a different MBC.

 

[sleepyvr4]

slowboy has those adjustable wastegate actuators. that'll probably cure your problems...

 

[CanadianTSi]

The fact that it opens early is the way it works...If it didn't Open untill your desired boost setting it would be to late and spike... By opening early it controls the boost just right and makes it level out where you have it set.