I ran through the process you outlined for me and have attached the latest tunes and datalogs.Personally what i would do if i were you is get the car warmed up and take a datalog with the new tune, dont make any tuning changes just datalog while do some engine revving. hold the engine at different rpm points do this a few times. then load the datalog into megalog viewer hd along with the tune file you used to datalog with. then run the VE analyzer, set the lambada delay to 3 and the "difficulty" to hard.
run the analyzer and accept the changes. Now save the tune file with the same name but rev.1.0.1 now load this new file into the car and do it again this will get the fuel really close to what the AFR table has set as values. Once you are all done (and the car still idles well) load the tune file you made all these changes to and a final datalog of the car running [do not make any tuning changes during this log] for us to review... I will then do some table smoothing for you and make a sanity check to be sure nothing goes south.
You could use ve analyzer live but to be honest i trust the analyzer in the megalog viewer much more.
I'm at the shop now and just took 2 datalogs running Rev1.0.3, one while warming up from cold (just idling) and one after already warm (varying the rpms).This fuel table may be a bit on the flat side, but what you had was wayy to choppy. give it a try and get a datalog.
Oops, sorry I posted a reply before I saw yours come in!Shoot for a stable 800-850 idle rpm with the valve unhooked. then plug it back in, i am going to adjust things one more time.
No problem dude, thanks for looking at them so quick!well i have to drive home, i will look at your files later. what i posted was a best guess from my end.
Ah ha, I did not have Idle Correction Advance added to MLVHD when I looked at the logs. It makes it obvious when it's shown there, and thank you for providing screenshots!look at the bottom graph see the yellow line, that is the idle correction advance, this is what was causing your timing oscillation and in turn the rpm hunting.
So does this means that the idle was "close enough" to what the base idle settings were so no correction was being added? Just to be sure I understand, is this defined in the "Closed Loop Idle Target RPMs" table? If so, I'm guessing it uses the last value on the right where the temp is the highest for the "warm idle" RPM or is that defined somewhere else?here we can see the timing settle down and the rpm hunting settled in step with it.
This makes so much more sense now! As I was trying to get the oscillation to calm down, I noticed that tweaking the timing in those cells in the main Timing/Spark Advance table didn't seem to make a difference. This must be because it was using the Idle Advance Timing table!This is in the startup/idle tab this is a advanced feature that allows you to set the timing based on load, i have set this to all 22* so at idle the timing acts like it is locked at 22*
I see, so to make sure I'm understanding correctly with your changes it will now not try to add/subtract timing unless the RPM deviates by 200 RPM? And now will only add or subtract 1 degree of timing rather than up to 2 degrees with the previous settings?now this curve is in the same area, this one adjusts the timing set in the first table based on how far the idle is from the set-point in the idle target curve. I have already adjusted this one to make it much less aggressive, this is what was causing the timing oscillation.
Do you recommend unplugging the IAC again and getting the idle to the target again or just go ahead and run the latest 1.0.5 with the IAC plugged in? If I can get it to idle at 850, would I just need to change the value in the Closed Loop Target RPM table?Personally I would get it to idle well around the set point, once you have that done blip the throttle and maake sure the engine does not stumble or pass to far below the setpoint.
Sweet! I'm gonna put in new u-joints when I get there today so after that the car should be ready to test drive.You may need to give it more timing in the idle advance table it may also like a leaner idle its all up to what the car wants. After you have the car idle tuned the way you want it, drive it a little bit even if it is just down the driveway and back while datalogging. then run the analyzer with the difficulty set to hard. You are going to want to go into the advanced settings and set the minimum rpm above 1200 so it does not mess with the idle range you just spent so much time tuning.
Ok sounds good, thanks man. I'm guessing the most important things to keep an eye on are AFR and boost levels for the first drive? Making sure it doesn't go too lean since there should be actual boost pressure now? I'll do a quick run down the street first and if that goes ok I'll venture out for gasThat's up to you, on the idle speed.
If you have someone that can come save you in case the worst happens yes drive it there and datalog the whole thing. Then send me the log and tune for review.
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