My Megasquirt adventures over the years

goldduster318 said
Having "mostly read" this, I honestly can't believe you had so many problems and are digging into some of these tables so much. I've had MS3 Pro on my 340 for 10 years a month from now. With multi-port, coil near plug, cam and crank with sequential injection and spark. It was very very easy to get it "good enough" and not have many quirks straight from the beginning.

Almost all tuning I did was in the VE table, Spark Table, IAC table (IAC target with temperature) and the PID. My car basically just works and other than occasionally surging when you tip in an extremely small amount at a low speed with the clutch out, I can't complain. Even got 21 mpg doing 75 on the way to power tour and 19 average on the trip.

My car has all GM sensors other than the crank sensor (Ford Ranger) and the Cam sensor (5.2 magnum distributor base). I understand some of the things about the Dodge specific sensors and all that but for example you can send injectors out to be flow tested if you don't know.

For the A/C I just use the A/C idle up to add 150 rpm. The PID is able to deal with any deviations and gets to the target fairly quickly with "Engine States" known. Heat soak doesn't seem to bother mine whatsoever anymore. I had too much prime at high temperature, which is how I dealt with it, it acted like it was flooding.

I am even using overrun fuel cut, controlling the fans, controlling the reverse lockout for the T56...I have ground speed control included as well.

Honestly, I probably make it sound worse than it is. I was actually basically in the same boat as you, though I went through the MS upgrade path instead of starting with all the bells and whistles from the get go. I could have really just left it alone after I did the MS3X upgrade and got it running and never worried about it again, but I wanted to make it act as much like an OEM computer as I could. The car always felt just a little less smooth than the other modern Hemis in the family fleet that I've driven. I was mostly just writing all of this stuff up because I found it interesting and wanted to share everything I had learned over the years. I also basically get 1.5-2 hours of tuning time in every day as I drive to work and back, so it's just been free research time to try out new things and really get things dialed in.

I know at this point I'm chasing that last 5% or something like that in efficiency and general "good running" stuff. My latest commute numbers have got me at ~22-23 mpg door to door round trip, which is probably more like 25 mpg highway and 18-20 mpg in town, depending on traffic. The whole thing just also feels like it runs much smoother. The main "issues" I've had have just been my AFR numbers floating around as the ambient conditions change. The car still runs fine and if I didn't have the gauge to look at I'd probably never know any better. Mostly just trying to really dial it in for fun now.

I also started with literally zero tune in my car. I bought the MS2 used, so I didn't have any kind of base tune to start with and had to learn from scratch.