Boost controller quirkiness?

[nikp]

"SET GAIN" is 0.57, "GAIN" is 0

[BlitzBoy]

wack the set Gain down to 0 as well, I will have another look at my controller tonight

[nikp]

Okey dokes - i\'ll try that.

[Prof]

\'set gain\' is what greddy call Start Boost - it holds the wastegate shut until it reaches that boost level - the value isn\'t really a percentage but a pressure - if you\'ve set the controller to measure in PSI, then it will be the PSI value, so 0.57 is 5.9 PSI.   The higher this figure is, the more rapidly the controller will build boost for you.
 
If gain is set to 0%, then the controller isn\'t going to make rapid adjustments - it\'s kind of like a slugishness factor - the higher the gain, the more rapid the changes the controller will make - but coupled with a high set gain this can lead to boost spikes.  You should increase the gain if the boost drops off or builds to much at the top end, but watch for spikes.
 
The problem you are seeing seems to be a bit odd - you get good boost built in low RPM, but less in higher gears.  I would check that you have the cables in the correct ports on the solenoid, and that the unused port has the plastic cap removed - that\'s important - it\'s where the pressure is let off from the wastegate.
 
For Internal wastegates - the actuator sits on the COM port, and the NO port connects to the boost source - usually a nipple on the compressor - NC port is left open to vent pressure of the actuator.
 
For External wastegates - the NC port is used and NO is left open

[nikp]

The problem you are seeing seems to be a bit odd - you get good boost built in low RPM, but less in higher gears. I would check that you have the cables in the correct ports on the solenoid, and that the unused port has the plastic cap removed - that\'s important - it\'s where the pressure is let off from the wastegate.

aaaaaaaah! I still have my plastic cap on. Is this really, really vital that it\'s removed? I will also double check the ports are correct.

The readings are in bar - so that was set to 0.57 bar to open the wastegate at.

[nikp]

Ok, i removed that plastic cap, and although i haven\'t had much of a chance to test it, have already noticed a marked difference. Even in second gear with those settings described above, i only hit a peak of 0.67bar, which appears, so far at least, a lot more normal. Hopefully it\'ll prove to be a lot more consistent in all gears now too.

[rx7veilside]

def importand to have the third port clear as i understand this is where the boost will bleed off and make sure it is facing down or put a nipple and pipe facind down to stop ingress of water and dirt..mine was badly fitted by nameless person next to turbo and with port facing upwards

[nikp]

I need to get a nipple for it in that case.

[nikp]

Ok, thanks for everyones help on this: I think this is now working correctly.

Unfortunately, i\'ve only had town runs to test it in, but it\'s looking a lot more normal now. I hit 0.79 in second last night, and followed that up with 0.76 in third, and considering that neither was taken to full revs, this is looking promissing. I\'ve also had to dial the \'SET\' value right up - from 12% to so far 28%.

So far, for low setting, I have:

SET: 28%
GAIN: 0%
SET GAIN: 0.57 (bar)
WARNING: 0.95 (bar)
LIMIT: 10%

So obviously i still have to do some fettling with the SET and GAIN values, but looking pretty good so far. Haven\'t had the chance to test it in 4th and 5th yet though.

[antnicuk]

glad you got it sorted