HOWTO: Select tune, ethanol content, variable rpm launch, rolling anti lag via cruise control

Roland@pcmtec · February 28

There are several ways to change tune and ethanol select in the Ford 15+ family (Mustang/F150/Explorer etc) with the PCMTEC MultiTune Custom Operating System.

With the engine off.

Accessories on (You will see a dash sweep, and then the previously selected tune/blend content, note you do not have to wait for this to finish)
Engine off
Cruise control on (press once)
Press Cancel (now in tune edit mode)
Press +/- to go from 1000 rpm, 2000, 3000, 4000 (base tune, tune 2, tune 3, tune 4)
Press Cancel (now in ethanol/blend select if you have it enabled)
Press +/- and you will see the speedo change from 0-100 (or 85 depending on your max value).
Press cancel again to return to tune edit mode or press cruise on/off to exit edit mode.

At any time wait 10 seconds (configurable via auF100029) for it to time out, or press cruise control off to exit edit mode. All adjustments are made immediately.

With the engine running.

Accessories on (You will see a dash sweep, and then the previously selected tune/blend content, note you do not have to wait for this to finish)
Engine on
Cruise control off (press once) - Note this is so that your cruise control still functions as per factory when the engine is running
Press Cancel (now in tune edit mode)
Press +/- to go from 1000 rpm, 2000, 3000, 4000 (base tune, tune 2, tune 3, tune 4)
Press Cancel (will exit tune select mode)

At any time wait 10 seconds (configurable via auF100029) for it to time out, or press cancel/cruise control on to exit edit mode. All adjustments are made immediately.

Adjustable launch rpm setpoint
For launch control adjustment (engine can be running or not running) select tune 1 (1000 rpm) press - (now in rpm select)
Now press +/- to adjust the variable RPM launch setpoint (if it is enabled).
Press Cancel to get back to tune select mode and re-select the tune you want.

Now if you want to be able to trim your blend/fuel whilst the engine is running we have a timer that allows you to do so. Previously this was 60 seconds by default (it is now 0.5 seconds), this allows you to dial in user flex and look at short term fuel trims if you are not confident on what is in the tank. During this time frame you follow the "engine off procedure". As this is not intuitive for most people (especially as most customers do not require this) we have since changed the timer to 0.5 seconds by default effectively disabling it by default.

If you want to re-enable this functionality (perhaps for demonstration purposes) you can reconfigure these timers to all be larger.

Eg:
auF100029 Maximum time to leave the RPM displayed after last tune change with engine running
This is how long the tune/blend ratio is displayed before it times out and exits. Default is 10 seconds.

auF100034 Maximum allowed time to change tune and fuel after the engine is running
This is how long you can use the "Engine off" procedure with the engine running to dial in user adjustable ethanol content. Default is 0.5 seconds

Note:
If you do not want the tune to change immediately when selecting it you can set the following scalar to 1. This will then only change the tune when tune edit mode is exited. This may be desirable if you have something in tune tune 4 but do not want to tune 3 to activate momentarily whilst you scroll through the tunes to select it.

auF100048 Confirm Tune On Exit (default 0)

Launch Control

Engine on
Press and hold the cruise on/off button.

This will activate the momentary launch control map whilst the cruise control button is held down. When it is released it will revert back to the map previously selected. If you have variable RPM launch control enabled it will also activate the variable RPM launch setpoint. By default this is soft rpm limit however it can be changed via various methods to be a hard cut or our soon to be released anti-lag spark retard/spark cut

As the launch map is simply a momentary map enable slot it can be used for anything. In turbo cars we find it most commonly used for rolling antilag or overboost (boost scramble). Eg you set up a retarded spark timing table in this map that pulls timing drastically to assist in turbo spool, usually dumping fuel, changing VCT timing etc. Or simply make it a copy of the "full boost" map and allow full boost to be achieved whilst the button is held down and only then.

For non turbo cars or cars that are drag raced and need a consistent launch, that is when we use the variable RPM launch control where it will hold the RPM at a variable setpoint (like the factory setup but without all the button pressing to enable it). In a manual car the factory launch control may be sufficient and not necessary. Simply using the rolling anti lag setup is a very effective "launch control" to get off the line with maximum boost, especially on cars with larger turbos that need assistance.

There are some guides for the Ford Falcon here, you can use similar principles with the maximum cylinder pressure timing map in the ecoboost motors.

In automatic cars setting up the anti lag with a spark hole as described in the guide above (depending on how far the standard stall converter will slip) is a great use. You can see several videos of it in action. We have seen a 4L turbo 6 with a GT3582 make 27psi in neutral with this technique.

Note

There are many other Custom OS features that can be configured under the CustomOS System Configuration -> CustomOS Cluster Configuration navigation tree. These allow you to adjust debounce timers to tweak how long the cruise control buttons have to be pressed, how many rpm/kph/mph each step is and min/max limits for various functions.