gt500 with VMP gen 1

[Devildog1325]

The car ran fine and tune was pretty spot on with just pulley, pmas intake, headers and full exhaust. I just put on a VMP gen 1, 10% overdriven crank, and ID1000's. Now I'm having a issue with lean tip in and rich tip out ive tried adjusting the intake manifold volume to help with the transient and it doesn't seem to really help. Has anybody else tuned for one of these. Ill post the tune maybe you guys can see something I'm missing.30.inj pres drop ref and manifold volume.hpt

[murfie]

Raise your clyair max multiplier up. You raised the cylair WOT already but not the max.

[Devildog1325]

Ok ill try that murfie you think that is causing the transient issue?

[Devildog1325]

Still having this problem seems like its worse when the care isn't all the way warmed up it takes a couple miles before it starts getting better. I have adjusted the time constant and seems to help some but doesn't help much when its not up to temp. Anybody else have any insight to this or a tune with similar mods that I can look at? I have seen some 3.4 whipple cars and the transient wasn't touched but everything in the speed density table was and I don't see a way to tune that without a map sensor.

[mstang_man]

check your MAF transfer function turn adaptive learning off, log STFT and LTFT/ basically 10% more air and tons of fuel.

[Devildog1325]

I tried upping my cylair wot and turning the anticipation back on and turning the adaptive off and it helped some but still having the issue I think my next step is going to be logging AFR vs Calculated Map and RPM and increasing the gain were its happening at and at what MAP value.

[Devildog1325]

Just and update. I used all the transient and manifold fuel settings from a 14 gt500 and still had the same issue. I logged my wideband vs Calculated map and Rpm and raised the gain for the cells that were leaning out. I also have to work on the startup gain table for when its cold so far everything has been responding well to this method it's just time consuming. Im also thinking experimenting with the slope and offset speed density tables from a stock 14 gt500 and turning the wot multiplier and max multiplier back to stock and seeing how that turns out.

[Devildog1325]

56. maf change transient adjust.hptFPVT tuning.hpltransient maf change.hpl

[murfie]

looking at your transient log your fuel trims are good. If you are wanting to adjust your transient tables maybe this info will help you. First the log shows exactly what you say and that is lean tip in and rich tip out.

Tip in- out.PNG

First you want to convert your wideband to lambda. Divide what the wideband reads by your stoich value 14.64. Then you can subtract commanded by that and divide by commanded.
O2 sensor error.PNG

Now you can use this to setup Two graphs to modify your accel gain and decel gain. Using a filter of the slope of engine RPM over a period of time(100ms) using greater or less than 0 to establish modifications to the accel or decel table. greater than 0 is accel and less than 0 is decel.

Transient.PNG

Apply the lambda error to appropriate table.

accel error.PNG

decel error.PNG

[Devildog1325]

Murfie you are the man! The way ive been doing it was time consuming and i still dont have it spot on and i been reading for days trying to figure out the proper way

[Exley]

looking at your transient log your fuel trims are good. If you are wanting to adjust your transient tables maybe this info will help you. First the log shows exactly what you say and that is lean tip in and rich tip out.

Thank you! Planning on dialing in my transients when it gets warmer out!