detroit pistins

iTrader: (102)

I am in the process of tuning my afr map, and been trying to lean out the spool-up area which seems to always encounter a rich dip when going wot. Mod list is hta86 on 93 oct @ 28psi, AMS F1, GSC S3, stock block, CB head, single wallboro+1000 cc injectors.

1) The feature “lean spool” in the stock ecu doesn’t seem to be activated since the rpm trigger thresholds are set to activate and disable at 1500. I haven’t played with this, but is anyone using it, and how are the results?


2) Actual wide band reading is off from the AFR target. I could keep on increasing the afr target until my wide band gets better, but is that the only solution? I wanted to check in case there is an enrichment calibration I am missing somewhere.



The run was a 3rd gear WOT and the engine rpm ranges between 2800-3500 and load is around 100-130.
Thanks for your help and feedback!

Ps. The map is still a work in progress so excuse some of the not so smooth areas.

Ian0611

iTrader: (41)

I have a similar issue just after I hit full boost (around 3700rpm). My AFRs always dip down to about 10.9 and jump back up to upper 11's by 4K. IDK what causes it. I tried messing with my fuel tables but it never made much difference so I pretty much ignore it now. I'm curious to hear what others have to say.

detroit pistins

iTrader: (102)

Would the VE map impact this?

foxbat

Is this MAF or SD?
Have you logged fuel trims to make sure that the injectors are well calibrated?

3K

iTrader: (9)

Even though your lean spool is set to start and stop at the same rpm, I would still deactivate it through the periphery.

detroit pistins

iTrader: (102)

I am on SD, and no i havent logged any of the trims. aren't the fuel trims more for steady state? When going WOT it should be in open loop, no?
and the injector scaling and latencies havent been touched. I used what was described in this thread for the 1000cc pte on 93 oct.
Thx
https://www.evolutionm.net/forums/ec...upermerge.html

Why? I would think its a good feature to take advantage of
Thx

foxbat

Published scaling & latencies are usually just ballpark values, injectors need to be properly scaled through latency logging or you might face some fueling issues including a significant gap between map & actual AFR.
However, since you're on SD, I think your issue might be VE related. I had an similar issue,but the other way around, I had lean AFR @ in low rpm/early spool area, I managed to fix it to some extent by adjusting the VE table & injectors scaling.

Lean spool is always a good feature to keep it enabled.

3K

iTrader: (9)

Because if you have your start and stop rpm set the same, your essentially deactivating the lean spool feature. I thought that was your intention. Therefore my suggestion.

07EvoIX

isnt this referencing accel enrichment?

cheers

detroit pistins

iTrader: (102)

Totally with you.....have new logs with trims and will make some adjustments.
On a side note, the way I understood the VE map is basically an offset to the afr map... So if I increase the values in VE then it should result in a richer mixture....Am I in the ballpark?
Thx


I may have caused some confusion with my question. I want the lean spool feature to turn on so I could adjust the flags and tune it, but I was wondering if anyone else is using it and how their results are....did it make a difference for them....etc

I think so as well, and I am hoping there is vector/surface that could be tuned.

foxbat

True... so, in your case, you could try & decrease the values (within the load range where the issue is) but only after you have fully calibrated the injectors.

detroit pistins

iTrader: (102)

Figured I would add a little update, I did find the enrichment table, its under the global fueling and seems to be a gain on the afr target based on rpm. I also adjust the injector latencies between 13-14 volts, along with small adjustments to the VE map and that seemed to have helped. Thx for your input everyone!