TermX tuning issue
#23
7 Second Club
iTrader: (7)
But it does matter, and depending on the combo it can just sit there and ride the minimum pulse width at idle and light part throttle cruise areas. Then you can run into injector timing problems with larger injectors if it's not done properly as well. Now whether the average person tuning their car will even realize these things is a whole different matter but I would say that most wouldn't even realize it because "it works". I tell people general rule of thumb is to target around 80% duty cycle for your combo/injector size to eliminate some of these possibilities.
#24
But it does matter, and depending on the combo it can just sit there and ride the minimum pulse width at idle and light part throttle cruise areas. Then you can run into injector timing problems with larger injectors if it's not done properly as well. Now whether the average person tuning their car will even realize these things is a whole different matter but I would say that most wouldn't even realize it because "it works". I tell people general rule of thumb is to target around 80% duty cycle for your combo/injector size to eliminate some of these possibilities.
#25
I have a termX on a 78 vette with a 5.3 and a summit stage 1 8719 high lift cam. Car is running pretty good where I'm driving it on the road to figure out all the little issues. This is not my first TermX LS setup as I have one in a 3rd gen firebird with a 5.3 and a turbo. My issue is at light throttle The engine revs/accelerates just fine through the RPM 3k+ through all gears (700r4). But when I give it more throttle say half or heavier after like 2000-2500rpms it like hesitates and breaks up basically falling on its face till I let out or get above that 3000-3500rpms. I also floored it when this happened and the car felt like it had no power but the car feels faster sometimes depending on when I stab the throttle and depending on the gear I'm in. I did a datalog of one of the runs and Its very weird... looks like its dropping out of closed loop and going to open loop? Then when I come off the throttle the closed loop comes back on. I verified the closed loop is enabled but it wasn't set to a min temp or rpm or anything... the closed loop box was just checked off. I set it to come on after 140*F coolant temp just like my other car. I'm not sure what is causing it to randomly drop out of closed loop but looks like it goes rich and maybe thats whats causing it to break up/hesitate and feel dead like RPMS and power don't climb. I'm not the best with the holley data logs but I attached it if someone could take a look. I also adjusted my closed loop learn values from 50/50 to 15/15 as the tune fuel learn table only shows a 5-8% swing. My timing isn't crazy when the break up is happening like 22-25* If I remember. Its also like my fuel lb/flow drops too like its cutting fuel?
Let me know what you think and what would be a good starting point. Like I said its only on med/heavy throttle and the car really drives fine otherwise (maybe a stall here or there every couple of drives) but I still need to adjust and get the IAC below 40 steps at drive idle.
file won't upload here so I added it to my dropbox. You can download the file here: https://www.dropbox.com/scl/fi/ungco...=ux5bpinp&dl=0
Here is the tune file:
https://www.dropbox.com/scl/fi/41wxy...=puekx47n&dl=0
Let me know what you think and what would be a good starting point. Like I said its only on med/heavy throttle and the car really drives fine otherwise (maybe a stall here or there every couple of drives) but I still need to adjust and get the IAC below 40 steps at drive idle.
file won't upload here so I added it to my dropbox. You can download the file here: https://www.dropbox.com/scl/fi/ungco...=ux5bpinp&dl=0
Here is the tune file:
https://www.dropbox.com/scl/fi/41wxy...=puekx47n&dl=0
#27
TECH Senior Member
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Old Buzzard (07-11-2024)
#29
7 Second Club
iTrader: (7)
Finally had a chance to look at this as well, looking at the last zip file that was posted...
- Upgrade your software, it's V1 which was released in 2019 I think and currently it's V3.
- That timing table is very generic and has way too much timing in the low RPM at high load and not enough timing at low/mid/high RPM at low load.
What you described here, "My issue is at light throttle The engine revs/accelerates just fine through the RPM 3k+ through all gears (700r4). But when I give it more throttle say half or heavier after like 2000-2500rpms it like hesitates and breaks up basically falling on its face till I let out or get above that 3000-3500rpms. I also floored it when this happened and the car felt like it had no power but the car feels faster sometimes depending on when I stab the throttle and depending on the gear I'm in. I did a datalog of one of the runs and Its very weird... looks like its dropping out of closed loop and going to open loop? Then when I come off the throttle the closed loop comes back on."
Do you have an instance of this in your last zip file log? Give a time stamp of where if you do. What you are describing is more than likely acceleration enrichment or MAP/TPS rate of change disabling closed loop.
- Upgrade your software, it's V1 which was released in 2019 I think and currently it's V3.
- That timing table is very generic and has way too much timing in the low RPM at high load and not enough timing at low/mid/high RPM at low load.
What you described here, "My issue is at light throttle The engine revs/accelerates just fine through the RPM 3k+ through all gears (700r4). But when I give it more throttle say half or heavier after like 2000-2500rpms it like hesitates and breaks up basically falling on its face till I let out or get above that 3000-3500rpms. I also floored it when this happened and the car felt like it had no power but the car feels faster sometimes depending on when I stab the throttle and depending on the gear I'm in. I did a datalog of one of the runs and Its very weird... looks like its dropping out of closed loop and going to open loop? Then when I come off the throttle the closed loop comes back on."
Do you have an instance of this in your last zip file log? Give a time stamp of where if you do. What you are describing is more than likely acceleration enrichment or MAP/TPS rate of change disabling closed loop.