MoTeC Global Forum

Hello

I had my car on a mates dyno yesterday, I have owned the car since February and I just wanted to check ignition timing, fuel and boost

All looked ok in his opinion, but it was down about 1.5psi in boost from the original dyno sheets I was given, as I had added a front mounnt intercooler, and also a process west intake manifold

Vehicle in question is a 2016 Subaru STI, built motor, FP Green turbo, and all other suporting mods to make 300+kw at the wheels on e85

We ended up at 270kw on BP98, turbo was pushing around 23psi, and the ignition timing was hovering around 11.1deg.

He had a couple questions for me to ask here and they are below

*****Boost Control Topic*****
- Aim difference
When ramping up the vehicle we noticed a difference of around 1.7psi at all times, we were using the boost control aim main table to increase the desired boost pressure, however there was always a differance of almost 2psi between actual boost conrol pressure and boost aim, see attached image, we were demaning 25psi but getting around 23.2

- Boost Cut
Where is boost cut limits within the Motec M150, so we can check that it's working

*****Ignition Cylinder Knock Levels*****

- Kncok Threshold
Noticed a very large difference between knock level and threshold, I was advised to lower threshold percentage lower in order to catch knock if occures

- Flex Fuel
Flex Fuel is enabled, yet to ramp vehilce on e85 as it's hard to get, but could this be contributing to the above boost control aim numbers not matching, as when its on e85 it will be demanding more boost pressure & timing, or am I wrong in thinking that?

I plan to go back there in a month to have the e85 side of this flex tune checked

some images attached, please click on them to expand them

Hope to get back some solid information in reagards to the above

Boost Aim can be limited by a number of other subsystems.

The limit is applied as a percentage of the current Boost Aim Main.

Boost Limit will indicate the current percentage limit, for example 100% means no limit is applied where as 50% would indicate the actual Boost Aim value will be 50% of the Boost Aim Main (other subsystems such as launch and anti lag can also override the value from Boost Aim Main but lets ignore this for now)

Boost Aim State will indicate the origin of the value of Boost Aim.

If Boost Aim State is Limited then Boost Limit State will indicate which subystem is currently imposing a limit.

Boost Maximum would be the boost cut value, if Boost Pressure exceeds Boost Maximum then boost control is disabled and the fuel outputs are disabled.

The Knock Threshold must be exceeded by the Ignition Cylinder N Knock Level in order for the Knock subsystem to retard the ignition timing, Knock Trim Gain controls how much of a reduction in ignition advance is applied.
This should be configured by the tuner using additional audio knock detection equipment

If a fuel composition sensor is configured and Alternative Fuel Mode is set to Flex Fuel then all the parameters within Alternative Fuel define how the fueling and ignition timing are influenced based on fuel composition (unless the help states the parameter is only used for Secondary Fuel mode)

Fuel Composition Boost Limit controls the percentage limit applied to the Boost Aim based on the measured fuel composition.

As this is a Powertune Australia Firmware, you will need to speak to them for support on this issue, as they make changes to the operation of the Boost control in their Firmware.

The biggest issue there is having to deal with Power Tune Australia, kinda getting sick of that answer sounding like a broken record.

They want $2500 to retune my car, zero help given as I was not the original purchaser of the ecu

I understand everyone has to make money & nothing is free but they wanted to sell me 10 hours dyno labour

Little frustrating that they have the monopoly in Australia.

I had a issues with Powertune software aswell. ended up buying another GPR package from another tuner and migrated tune across. Could be a viable option as its a bit cheaper than 2500 and you keep your tune without the Powertune locks on it.

Quick update on this post

I got Powertune Australia to update the firmware in my M150, this has fixed a lot of small issues with boost, control and launch control.

Unfortunately it’s playing havoc with my AC just something else for me to fix