adjusting Power enrichment table - SRT Forums

95Neon R/T · 05-04-2009, 04:40 PM

ok, so i have 11.9 comanded throught the power enrichment table.

At the moment in boost i am between 11.1 and 10.0

If i want the power enrichment values to actually be what is commanded should i go in and edit the VE table in the boost areas?

SRT-What? · 05-04-2009, 05:52 PM

poeple are going to tell you to get the LTFT right first. Than proceed with the PE table. I don't remember in which way to increase/decrease, but I'm sure somebody knows it.

julius717 · 05-04-2009, 07:15 PM

Quote: Originally Posted by 95Neon R/T

ok, so i have 11.9 comanded throught the power enrichment table.

At the moment in boost i am between 11.1 and 10.0

If i want the power enrichment values to actually be what is commanded should i go in and edit the VE table in the boost areas?

from what i understand you have to adjust untill you actually see it on the wideband. make sure your sensor is good and you should be fine. i dont remember where i read it at but i did read it

apexcrazy · 05-04-2009, 07:55 PM

The SCT wiki has this info . but if my memory serves me right , in an theoretically perfect world a value of .0158 in the WOT power enrichment table would get you 11.8 afr . As previously stated your injectors must be scaled correctly before you attemp to adjust this tables . these are WOT only values , & WOT is open loop operation , so it seems to me your LTFT wont adjust the injector flow at certain large pwm values , if your ECU doesnt see them in closed loop , ever , how can it adjust the fuel charge at that commanded pwm ? I may be wrong on this . Im having the same problem with my tune right now , Im as low as 0.0100 in certain areas of my PE table . But im still getting low 10 AFRs sometimes at WOT . all my exhaust/rearO2/cat temp modifiers are disabled , so im going to rescale my upper pwm vs. fuel charge values to see if that helps .
There is a WOT voltage scalar under misc. that may be the open/closed loop switchpoint . the stage2 flash has this set at .9 volts .

in the stage0 it has the same value as the WOT power enrichment voltage ( 2.333 ) . I have wondered if its possible to up this to 3 volts , so you would stay in closed loop , thus allowing the LTFT to adapt injector flow . But thats another topic . Datalogging would make tuning this shit soooo much easier . C'mon SCT !!!

95Neon R/T · 05-04-2009, 08:25 PM

i have stock stage 1 injectors so they are scalled perfectly.

It would be nice to have the LTFT adapt for boost but if you stay in closed loop it will always reference the Stoich value and never reference the Power enrichment table.

LTFT are within +/- 5 btw

My wideband it brand new and works perfect.

If i adjust the Power enrichment table i do see changes in the AFR but i would like the to actually represent what they are so i thought i could set the Power Enrichment table and then go in and tweak the VE table to get them to match.

Also ATM it is 11.5-11.6 up to 10 psi and then 10.5 from 10 psi to 14 psi.

apexcrazy · 05-04-2009, 08:50 PM

Quote: Originally Posted by 95Neon R/T

It would be nice to have the LTFT adapt for boost but if you stay in closed loop it will always reference the Stoich value and never reference the Power enrichment table.

Im not sure about this . There are two places in the code you can ajust WOT voltage threshold . One is under the fuel section , the other one is under misc. So if your WOT power enrichment voltage scalar is set to a value below the MISC. WOT voltage threshold scalar , it could be possible to enter PE while still in closed loop .
This is assuming the open loop , closed loop switchover point is controlled by the MISC. section WOT voltage scalar . I have never seen an explaination for this WOT scalar .

95Neon R/T · 05-04-2009, 10:00 PM

true, but what good would a narrowband 02 sensor be in closed loop at values richers then 14.7

apexcrazy · 05-04-2009, 11:27 PM

Quote: Originally Posted by 95Neon R/T

true, but what good would a narrowband 02 sensor be in closed loop at values richers then 14.7

Not much . But Im running stage2 code . IF the MISC. WOT scalar is triggering open/closed loop mode , then it is occuring at .9 volts .
this would imply that stage2 is going open loop at 1/3 throttle . Which would imply that the LTFT cannot "adapt" fuel flow when above 1/3 throttle in stage2 . This seems to explain why I have never seen my upper range LTFTs move off 0.0 . But if I raise this to 3volts and keep engine load light , I might be able to get the LTFTs to adapt beyond 1/3 throttle .
In stage0 MISC. , min voltage for WOT is set to 2.331 . In a stage0 3bar rescaled flash I made , my LTFTs seem to work higher up pwm range , is this due to higher min. WOT voltage ? or was it just my rough injector rescale ?
I dont know . there is no user manual for this ECU . there is no datalogging on the SCT yet . There are tables in Advantage III that are labeled wrong . there are settings that seem to contradict themselves . There are acronyms that are never explained anywhere . there is no good way to nail down all these damn variables other than cautious experimentation .

apexcrazy · 05-05-2009, 10:17 PM

Ok , i was checking my LTFTs at large pwm values today , & the ECU seems to be staying in closed loop above the MISC scalar , Min WOT voltage . I am seeing the LTFTs adapt above voltage value here .
So I think you may be right , perhaps the ECU stays closed loop untill you reach the WOT voltage for power enrichment . Anybody know for certain ?
Anyways , got my AFRs to stay in the 11s for the most part .
I think I may be maxed out untill I get a better exhaust . Or start tuning for an E-85/premium mix .