Last post for the night. I drew the lines you demonstrated and then compared it to the other procharger tune I have. They are actually of a similar shape with your design being smoother and slightly more aggressive numbers on exhaust. So I'm getting the general feel of what needs done and for sure some more reading will help that along. Still a ways before I get the method to picking where the numbers fall.
FOr the tip in. I have the below chart. If varies from stock only in that the middle value went to -2.5 to help there last year sometime. I think you're saying re parse this table from 1k to say 5k - that's where a redline shift falls to. and then just tweak the -2.5 til it settles the knock down?
I tried the VCT profile you drew - just to and from work. It didn't like being so aggressive in the low rpms. stft's would shoot way up and the car would bog - really similar to when the Pedal counts for WOT were low. I put it back to what was before and the problems ceased. So I'll post up the logs. I don't understand the why of it yet but it feels like this jerky curve I've got makes the car run pretty well. The real frustration is with spark. the tip-in knock is gone. yay. The off throttle decel knock is driving me bonkers. The car really likes more timing than these last few tunes but it keeps polling positive knock on decel so even tho the numbers are super conservative now... it still shows knock randomly on different logs. can't get it blocked in. I'll post up two tunes and logs. One with the aggressive VCT and one without. I don't have a lot of time tonight to mess with it. I read the link you sent and I followed it pretty clear - but this car just wants to be weird about applying it.
Oh, right - forgot to ask. What PID or maths do I need to Poll VE? There isn't one named VE or volumetric so I think it's more complex than just scanning the pid and making a graph.
Yeah looking at you you only changed the OP tables. The drivability distance table and mapped point values were much more important for the lower RPM changes. I say if the current VCT is working well maybe just stick with it unless you wanna play around figuring out how to make the car play nice with them.
For the decel knock you have the decel spark advanced table to make changes. The other thing is your DFCO is not working. The settings you have for it are stock. The only thing else I have see cause this are the cylair WOT and MAX multipliers. another change from the cook book that is not fully and clearly explained just proposed as necessary.
I have attached some Maths for calculating air mass from a MAF sensor and a MAP sensor or their inferred values. From here ford uses a quadratic regression to estimate their speed density calculations (haven't figured out how to do this in the scanner yet). The engines VE is basically the mass of air its moving relative to the theoretical maximum. So if you see more air mass you are at a higher VE. Note: The multiplying value in the bottom of the MAF one is half the number of cylinders AKA compensation for 4 strokes or 2 revolutions. This may not apply to flat plane crank applications.
If you look at these maths in a chart if you notice the MAP(inferred value in your car) is about half the MAF. Your multipliers for the speed density are 1.99. you can try lowing this until the MAF air mass and MAP air mass are much closer.
When using these maths you are working with a small value. so make sure you use a decimal value of like 5 or 6. HPT scanner seems to have a bug with these small numbers where after you enter the .004 in the maximum you need to enter 0 in the minimum before you see it in the chart correctly.
Oops. I see the issue. I thought both paragraphs were related to OP only - getting it above drivability. I definitely want to play around with it at some point to see if there is a bit more low-end. It's going to rain til the weekend and then racing. It will have to keep. I will reduce the cylair wot stuff down. I'm pretty sure we've filtered out all of the handbook changes and it's back in line with the tuning school and your input. I'll look into this VE stuff after the weekend. I would really like the spark to be a bit better. as a new attempt, I took the Indicated torque by MP charts and made a new set for Spark by MP. there were a couple places where the MP do need to be unique instead of spamming them all as OP. But what's weird is that when it is in OP at or above 100% load the spark is higher than commanded while still showing a couple degrees of knock. It's baffling.
It seems like this takes such a long time to do! Even without the learning curve. It would be fantastic to do this on a Dyno. parts of it would be faster for sure, more accurate. BUt it feels like I would need two full days just to get through spark and VCT taking my time on a dyno rental. And there's always the chance that you get "stuck" and the car can't move for whatever reason. I don't like putting people in that bind. How long does working up a tune usually take?
VCT would be the only thing you could really use a dyno for. some tuners spend a whole day on it. I think in less than four hours you could really see 90% of the improvement you are going to ever see. you could spend 100 hours working on that extra 10% and never really make a dent in it chasing your tail. The tricky part is you need to watch everything as a whole on every run. Then you need to allow cool down time if air temps or CHT start getting too hot.
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