Twin Turbo Megasquirt Tune

[MyTurbo3.6]

After spending some time on the dyno and tuning my megasquirt, thought I would share my current files.

Car starts easily, idles perfectly, revs freely and AFRs remain good throughout the entire powerband.

Would appreciate a critical eye and feedback on areas to tweak and improve...

MSQ File https://www.dropbox.com/s/3qa83s4zclghzzs/DGTT%20PRT%20Tuned%202014-09-24_09.03.38.msq?dl=0

[turbobrat930]

Not familiar with MS, as far as their setup. Is there a master fuel setting? ( a numer you can change to add or take away fuel from the whole map at one time)

[Tippy]

Yes, it's called "req_fuel". Or, you can highlight the entire map and hit the "*" button at the top right and multiply by 1.X or 0.X.

[jsveb]

I can't help you, but I just want to say, I so appreciate that you share your experience, files, online for others to learn.

Good luck!

I hope I will need them some day...

[hobieboy]

I am chasing a severe misfire issue at high boost + >4500RPM with my MS3 set up.
I noticed that you are running a LOT less timing than I do - I only retard to 16 degree at 6500 RPM range and in the 160kpa/4500RPM range I'm still running ~20 deg.
Did you have to pull lots of timing when you started tuning?

[xbmwguy]

Seems extremely low on timing. Your afrs and fuel are extremely close to my ms3#s

[Tippy]

I am chasing a severe misfire issue at high boost + >4500RPM with my MS3 set up.

I noticed that you are running a LOT less timing than I do - I only retard to 16 degree at 6500 RPM range and in the 160kpa/4500RPM range I'm still running ~20 deg.

Did you have to pull lots of timing when you started tuning?

Have you tried closing the gap on your plugs to say 0.020-0.025"?

High boost can suppress ignition.

[Tippy]

Seems extremely low on timing. Your afrs and fuel are extremely close to my ms3#s

Me too. I run pretty close target AFR's

I'd say get rid of the 20.0AFR's in the light load areas as it will run really erratic. Maybe 16-17's tops.

I tried running super lean, but with really advanced timing, it makes the car run bad.

[jpnovak]

Wow. Are you running 2 bar of boost (300kPa)?


What is your engine spec? That would help put the tune into context.

It just seems to me that the fuel requirements are quite low on your VE table when under boost. Usually there is a sharp increase in fuel delivery when the car comes on boost.

[Speedy Squirrel]

These are my opinions/conjectures.

I presume that you have 10 degrees static timing, and you left the offset at zero? Normally, one would set the static at 10 and set the offset at 10. In that way the timing values in the table would mirror what you would see with a timing light.

What range do you run closed loop? I like to cut it off at 3100 and about 80 kPa, basically just the lower left corner, the cruise region. Obviously, the AFR targets beyond the closed loop region are meaningless then.

The VE table should continue increasing the VE's out to the highest RPM. I presume your over-rev point is around 5800? If you should accidently find yourself over that at WOT you want to make sure you are overfueled, not underfueled. If everything is working, the ignition rev limiter will cut off the ignition before you ever get there, but if you do get there, you want to be overfueled.