MSgpio.com read only forums (Jan.15,2018)

Am curious if there is a way to command something lower than 40%? According to the documentation, it looks like it is hard coded as 40%. I installed a shift kit in my transmission years ago. Part of that "kit" was to tweak the adjustment screw on the PC solenoid a quarter turn to increase line pressure. So... when I command 40%, my line pressure is around 100psi. I would like to be able to command something less than 100 psi, especially when in neutral, to soften the engagement into drive.

What do you think?

Dave

Dave,

If I recall correctly (I haven't looked at the code in detail for this in a while), the 40% limit is entirely in the INI. To change the limit, you need to find all the places in the INI it s specified and change it. This would be things like:

...

etc.

You change the value of 40 to something lower, and I believe it should work. In the meantime I will look for anything in the code that might interfere.

The lower limit of 40% is there to prevent people from burning up there transmissions internally (both the friction elements and the solenoids themselves from the higher current). But if you know what you are doing, you can probably go a bit lower.

Lance.

I had a quick look in the code and I don't see anything that would prevent PC duties lower than 40% (i.e. PWM% higher than 60%) in the code itself. So the INI changes ought to be enough.

I'll give it a shot tomorrow. Thanks.

Dave

Lance,

I tried what you suggested. After making the ini file changes, I was able to make the changes to the Tuner Studio input window. But there still appears to be a min floor logic occurring related to PC calcs when in Park. It would work for input of 41 and above, but when 40 or lower was entered, the PC% jumped up to 50%. Can you check the code?

BTW, 41% is still too harsh for me, when shifting out of Neutral. 41% for me generates 140psi.

Thanks,
Dave

Dave,

Can you post your MSQ/modified INI and a datalog? I will have a look in the code shortly.

Lance.

Dave,

There is one 'fail-safe' in the code that might be stopping the line pressure from getting low enough for you.

The code checks all the 16x9 cell values, and makes sure the final value is not lower than the lowest table value. This was put in to make sure that rounding errors didn't force the line pressure into an unsafe state.

However, this does not check whether you are in PNR first, and it should do that (so that user settings for these gears are applied).

I will add this shortly and post some code here - are you using 4.1xx code or the 5.xxx series of code?

In the meantime, as a work-around you could try lowering the lowest value in your shift table (perhaps one of the lesser used table cell values - like highest-speed lowest-load) to see if lower values are achieved.

Lance.

Dave,

Here is some test code:
This code only checks for the lowest table value when:
- the table is not specified to be used by the user in reverse, or
- when in a forward gear.
It never checks in neutral.

This code is completely untested, so use with great caution.

Lance.

>>are you using 4.1xx code or the 5.xxx series of code?

I am running 4.137. Haven't made the jump to 5.xxx due to the heavily customized ini to get line press and oil press (Aux) calibrated.

I'm still about a week out from getting this thing on the street for first drive, (for other reasons), so no rush.

Dave

Thanks Lance. I'll try the 4.138 here in a day or two.

Dave