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Bdirtymax

Member
Feb 5, 2016
55
0
6
Grand Rapids, MI
Can anyone tell me why I'm getting more boost than what is being commanded? This area of the tune is only at 25-26 psi and it's pushing almost an extra 10 psi for some reason. My boost gauge shows it and this log shows it. The only limit table active is actually pulling about a 1/2 psi of boost in this range. I opened the vanes up from stock to 35% thinking that was causing it but it's obviously running off the transient table so I'll change that one as well. Is it just the cold air compressing more and causing it? If it is something like that I'm ok with that. But if not, I'm out of ideas on this tune.
Thanks
 
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SSchmi5519

SSchmi5519

LLY Cult Leader
Oct 19, 2008
3,387
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Arizona
There are many multipliers and modifiers that affect the desired boost and vane tables in regard to current coolant temps, intake temps, barometric pressures, etc etc etc.

If you are wanting less boost then the easy way is to change the base desired boost in those specific areas until you get what you want.

Or go hunting for modifiers. :thumb:

Good luck!
 
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Bdirtymax

Member
Feb 5, 2016
55
0
6
Grand Rapids, MI
SSchmi5519 said:
There are many multipliers and modifiers that affect the desired boost and vane tables in regard to current coolant temps, intake temps, barometric pressures, etc etc etc.

If you are wanting less boost then the easy way is to change the base desired boost in those specific areas until you get what you want.

Or go hunting for modifiers. :thumb:

Good luck!
Click to expand...
I have all the multipliers and modifiers covered. ECT Mult is at 0, IAT is at 1 and the Multiplier is at -.1904. TVTP ECT is at 0, IAT is at 9 with a multiplier of -.2253. It still only commanding 24.94 psi of boost. It is pushing 33. The vane position is where it's at from the TVTP T/R during shifts table which is stock. Looking for more of a reason besides the multiplier tables that would cause it to create 10psi more boost than commanded.
Thanks
 
B

Bdirtymax

Member
Feb 5, 2016
55
0
6
Grand Rapids, MI
BigTexas68 said:
Are you referring to the boost2_DMA pid line? If so I believe you will have to subtract atmospheric pressure to get actual boost.
Click to expand...

Yes I know. It's commanding 25 psi boost which would be 11 psi on my boost gauge here. It's actually producing 33 psi of boost which shows up on my gauge as 19 at this particular spot. It goes to 185 KPA / 26.83 psi commanded and actually produces 36psi and shows on my gauge as 22 psi.
Thanks
 
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Bdirtymax

Member
Feb 5, 2016
55
0
6
Grand Rapids, MI
Killerbee said:
Are you sure about your PID accuracy? It looks to me like your boost is (28.1-14.4)=13.7 psi
Click to expand...

I'm not sure if the PID is accurate but it is commanding 172 KPA which should be 24.94 psi which matches the boost table should be 10.54 on my gauge. What it is showing as boost pressure which matches my boost gauge is 33.1 psi -14.4 = 18.7 psi.
Thanks.

I think I found the culprit table. I'll log it again and confirm.
 
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