Turbo Tuning MoTeC M1 PID

Hi, perfect webinar!

At first necessary to get fine tune (fuel and ignition) in all map cells with low boost (turbo - spring setup)

After that starting to find necessary boost levels with best DC for boost levels (open loop)

From how much throttle position would be best to start going up in boost (more than standart - spring boost)

AIM boost with more solenoid DC start to achive with 70-80 % of throttle?

What suggestions?

Using Motec

Thank You!

Hi, thanks for your comments.

If you jump into the upcoming webinars section, you will see that we are running a webinar on setting up boost control in the M1 on February 25th. This will answer all your questions i believe as well as showing you how to approach the tuning.

In general I suggest starting with your PID settings set to zero to force the ECU into open loop. From here we set the feed forward table to achieve as close to target boost as possible. Next you can start adding in some P, I and D gain to help correct any error. Most people make the mistake of not spending the time in the open loop table and hence the closed loop system has more work to do. This makes it much harder to achieve smooth control.

Hi Andre,

I just watched your webinar and have what is likely a stupid question. I'm using motec m130 in an evo x and target boost is 28.5 psi on my pump gas tune my boost aim is in psi and my proportional gain is .8 % kpa. Does that convert automatically to a psi value or do I have to manually do that? I just want to make sure the different units aren't causing an issue as I have about a 2 psi boost spike and the proportional gain goes up and down in my log before settling and I wonder if that could have anything to do with it. What proportional and derivative gain would you recommend for a 2.2 stroker with a 57mm turbo (efr 7670). I'm using P .8 and D .1 at the moment.

The units of boost aim dont matter, the proportional gain is still relative.

You really need to attach your package and a log file. Although your proportional gain does sound a bit higher than typical, it could also be a multitude of other settings besides just prop gain. It could be your margin too small, activation too high, feed forward incorrect, etc.

Thank you for responding so quickly. Attached please find my current package and some log files.

To me it appears your boost margin is too small so the ecu has disabled boost control and is holding the wastegate fully closed until you are too close to the target so it overshoots.

Two ways to fix this - the quick fix will just be to increase the margin - try it around double its present setting. The more correct fix would be to make your boost aim main table more realistic, and it may still need more margin as well. i.e you have a boost aim of 35psi at 2000RPM, this is never going to happen, this table should follow the achievable boost curve better.

I suspect the PID will still need work after these changes but you need to get the basics right first.

Thank you. I will try those changes.

One addiotnal question. Previously I had the boost margin at 14.5 psi and the wastegate would remain at max (60%) until the same spot in the log, could that be because the boost aims are too unrealistically high or do you have other ideas?

Hard to guess without seeing a log. With the aim set much higher than can be achieved and a large margin which enables the control early then you would tend to get integral windup, which will usually cause overshoot.

Updated log and package attached. Much better results. Have any thoughts on more PID changes or temp based comp or anything else?

Also, I have an old aem boost gauge still hooked up and it registered about 3 psi higher in the log with colder Temps. I would trust the motec I presume. Yes?

Updated log and package attached. Much better results. Have any thoughts on more PID changes or temp based comp or anything else?

Also, I have an old aem boost gauge still hooked up and it registered about 3 psi higher in the log with colder Temps. I would trust the motec I presume. Yes?

My feeling is there may be too much derivative. I would try about 2/3 the current value. You will probably have to reduce P once you take some D out too.

Thank you. I will give that a try.

So i've been playing around with P and D and finally got the boost where i wanted! Thank you guys for the above advice, really helped. I recently had another issue. My idle got very rough after a drive recently. It stayed rough like this (and died a couple of times) for about a minute or 2. I noticed that the motec was displaying 0 on the afr when this was going on for part of the time (see attached video) also the attached log shows the throttle position moving constantly. I turned the car off a couple of times and on the 3rd or 4th try it started to act normal again. I'm a bit concerned and thought maybe it could be a loose connection of some sort or a bad LTC (i will test that next). Based on the log and the video what do you guys think? any idea what 0 on the afr reading means? the afr started reading again and the problem persisted, the afr was jumping around a lot. Before this my idle was pretty smooth considering the cams etc and there have been no changes to my tune or to any parts in the car since then and when the issue appeared.