944T Launch control

[George Elliott]

I have read the ECU thread today Barks, and what you are developing is really impressive.
Can we spec up our requirements any time now?[]
Keep up the good work
George

 

[barks944]

Actually I would be very interested to know what you would want from a new EMS, even though I'm not quite ready to produce the end product! I've written down some features for what I want to be able to support but it would be nice to know what a potential end user would select from that feature list.

 

[George Elliott]

I would seek advice from a couple of respected sources before setting the final spec, but if the sky was the limit I would be thinking along the following lines:

Inputs:
TPS
MAF/MAP
Crank Position
Road Speed (front wheels)
Road Speed (Rear Wheels)
Boost Pressure
Knock detection
Lambda reading
Water Temp
Ambient temp
Amps / Battery Health
Wipers on / off (with 20 minute delay feature)
Limited Mode Switch

Outputs:
Ignition spark
Fuel Injectors
Wastegate control
Warning (existing central Red Dash Light) - Knock/Water Temp/Rev Limit/Low Oil Pressure/Lean running

Control Features:
OK, I want maximum power up to the Boost pressure set on the Boost Controller (that is the basic ECU mapping)

Closed loop Ignition and Boost control for Hot weather, and variable fuel quality

Cold Startup Map - enriched mixture setting

Rev Limit restricted to 3000rpm until water temp at Normal

If the road speed (front wheel average) is below 20mph I want a 50% boost reduction enabled, below 30mph 40% reduction, below 40mph 35% reduction, etc regardless of gear ratio. (maybe analogue IO is best for this 4-20ma range etc?)

If the rear wheels ave speed exceed the front ave, there should be a "soft" torque reduction feature to regain traction without throttle readjustment (again closed loop - mis one in 2, or 3, or 4 sparks / fuel injection deliveries - according to front wheel speed, high speed will require less torque reduction etc)

If the wipers are on, or have been in the last 20 minutes, lets have a 30% boost reduction to be enabled automatically - this times out after 20 mins. (if we use the wipers accidentally in the dry - tough cookies for 20 minutes)

If the ambient temp increases above 28 degC, or water temp is above ?degC, the boost is limited to 0.8 bar

With Limited mode enabled, the boost is restricted to 20% (for when the kids wash the car[])

Anti-lag, a pattern of closed throttle inputs from the TPS coupled with reduced wheel speed inputs, enables a series of fuel injector deliveries, which ignite in the crossover pipe and spin the hotside impeller. Unfortunately this may produce an exhaust flame[8|]

Thats enough for Phase 1, Torque vectoring is another consideration when this is all working. Then we need a car and Sabine to prove the technology against the clock[]

What is the objective? - the potential for a 1200kg budget Q-car with dynamics to rival Nissans GTR, M3, 575, GT3 (in the wet)

George

 

[barks944]

Ok, good feature list. Road speed is an interesting one, later cars have a hall sensor on the gearbox which I can use. For cars with ABS I might tap into the ABS sensors if its safe to do so. Once speed is into the DME its no problem to control boost based on speed or any other parameter such as RPM/Engine temp etc etc. Any parameter that can be measured can influence any output parameter. All the other inputs are covered.

Wastegate control is an interesting one. If you install an electronic boost solenoid its easy, whether you have a single or dual port, there is also route to using the original boost control setup but its a little hacky and requires some changes to the KLR and the use of a lux DME rather than the turbos DME. It can be done though.

External switches/laptops or phones can be used for changing parameters. So you could switch boost and fuel maps on any of those interfaces. Switches could include a wiper switch or any digital input. Anti Lag could be interesting!