@SiriusC1024 Thanks, will give it a go this evening and get a longer log with steady pulls across more throttle zones. Did you change anything besides the MAF? What did you do to get to the updated values?
@SiriusC1024 Thanks, will give it a go this evening and get a longer log with steady pulls across more throttle zones. Did you change anything besides the MAF? What did you do to get to the updated values?
Last edited by flatpick13; 08-25-2024 at 02:14 PM.
Log file attached for that step 5 tune, whatever you did also seems to have fixed the values at the top end, still a few over 5 but most of them are less than 2%, I appreciate the help, if you can explain what you did to step it there so quickly i'd appreciate it! I'm still getting throttle hang, very little engine/diff braking when I let off the pedal and makes shifting rough over 5k rms, I have a feeling that has to do with the torque management....
I did it exactly like I laid out in Post #24Originally Posted by flatpick13
MAF should be there on this one. Log to check anyway.
Since you're still having problems it's looking like VVE tuning is required.
Clear LTFT's. Include Dynamic Airflow and Virtual Volumetric Efficiency Airflow in the log.
@SiriusC1024 Thanks again! I guess I'm missing how to do the piece about extrapolating to the upper and lower bounds using 1.05 for top and 1.02 for bottom. I fiddled with it again in the tune trying to go off of the screenshots you posted and nothing I did looked correct...
All values but one were less than 3%, almost all were less than 2%. Also funny story, there was still throttle lag but it was less after applying this tune. I did two runs, one to warm up for about 5 miles (not logged) before which I reset the LTFTs and at the end of that run the throttle hang was noticeably less. I pulled into a parking lot, reset my LTFT again and restarted the log, throttle hang was back but when I finished the drive (probably 4 miles) the throttle hang was starting to lessen again.
I logged Dynamic Airflow and VEs this time, tried to do some research on what graphs to set up but didn't have any set up for this log, I'll do another this evening with a graph for VE in percentage deviation per RPM.
Can you post a pic of the intake setup, please?
Got a link to the exact cams you're running?
Last edited by SiriusC1024; 08-27-2024 at 11:29 PM.
Pics posted, all custom to cram into the engine bay of a '96 Miata, there are two air feeds to the intake from the front of the car, IAT temps are usually pretty cool (at least when I'm moving).
IMG_5288.jpg
IMG_5289.jpg
Running mace cams, link here https://www.maceengineering.com.au/e...ducts/CAM669-A
Last edited by flatpick13; 08-28-2024 at 07:23 AM.
MAF honeycomb is still intact. I'm also having an issue with the car stalling sometimes when I clutch in or take it out of gear (i.e. stop signs), idle goes way low, sub-500 rpm, and sometimes it comes back up to 750 just fine and sometimes it stalls. Do you think changing my Dynamic Airflow disable points to maybe 1k RPM would resolve this? I wasn't having stalling issues before I dropped these to 200 and 100.
IMG_5291.jpg
Raising the Dynamic Airflow range isn?t the fix, that didn?t work, still stalling about 1/3rd of the time when I let it idle down with clutch in or out of gear.
So it's VVE tuning then. Expect it to run terribly at first.
Stay under 4000rpm's. Don't floor it. Smooth steady pedal movements. 15 minute log at temperature.
Add alcohol percentage if you have the FF sensor installed. If not I'll change it in the tune to disabled.
@SiriusC1024 thanks, I?m out of town until Tuesday but will give it a run when I get back next week. I do have a flex fuel sensor so will make sure alcohol % is logged. Is there anything else I need to enable/change/disable to make sure logs are good?
Oh yeah. Cylinder Airmass.
@SiriusC1024 Sorry for the delay, just getting out from under all of the catch up from being out of town, planning on logging some runs tomorrow but looking through the tune file change first, looks like all that changed is the dynamic airflow put back and the PE enable pedal % is cranked up, which makes sense why I need to stay below 4k rpm and not floor it so it doesn't run too lean. Anything else changed that I should be aware of before I log runs tomorrow? Already have a channel for alcohol %, will make sure I have cylinder airmass, any particular graph I need to set up so I get the correct log numbers?
You're good to log. No special graphs. It's the data collected that's important.
I enabled SD by setting MAF Fail Freq High to 0hz under the Engine Diag section. MAF will be entirely ignored. The Dynamic Airflow High RPM disable was put back to stock to keep things consistent in the tune.
Work has kept me from getting a run, seats are out of the car, will try to get brackets fixed and seats mounted so I can do a run tomorrow.
Sorry this took me so long to log, just got seats back in the car this afternoon. Log file attached, made sure alcohol % (I have an ethanol mix in, should be around 60) and cylinder airmass were logged. Wasn't able to get much throttle pedal movement as it would jump over 4k pretty quick if I did, it did cut power starting from a stop sign in first gear a couple times, but I never got close to 90% throttle.
That's alright. Use VCM Scanner>Vehicle Controls and Special Functions to clear LTFT's after loading this tune.
Should I do another log run staying under 4K with this one?
Yeah. You can go above 4k. Don't do WOT.
Ok, cool. Did a start today but nothing logged, leaving at o?dark thirty tomorrow morning for another work trip but should be back Saturday. Have a race the following weekend so hopefully can get it worked out, worst case will drop back to the last MAF tune for the race and then come back to tuning the VVE.
Ok, logged with the next step for VVE. Some observations: First gear cuts power with almost any throttle input above idle; still running fairly rough; still noticing throttle hang when I rev over 4500ish and clutch in to shift, or let off throttle.
Sorry about the delay in response/logs, busy season picking up for work has got me traveling more and busier than I'd like to be...
Reply With Quote