Engine Control

Engine Control - put under engine or leave separate?

• Theory - spark, fuel control
  
  • passive v active (wasted spark and carbs v PFI/DFI and spark control)
    
• Tuning
  
  • alpha-n
    
  • common ecus
    
• Custom cams
  

Theory

Passive

It is possible to run an engine without an engine control module.
Wasted spark such as yamaha wr450 before 2010
cbr is carb stock

Active

control spark - timing
control fuel - timing, duration (can't really change angle or placement so we put that under fuel system design, not here)
control air - throttle
control temperature - radiator redirect valve, fan control
control valve timing, valve lift (not electronically tunable, but still control, i'd be willing to put this under intake if that's a better place)

Tuning

Engine tuning is the idea of changing the independent inputs to the engine to achieve a desired goal. The inputs available to tune depend on the engine control strategy. Usually this goal is peak engine torque at every operating condition.

• engine control strategies
  

The most common engine control strategy (at least in fsae, not sure about the galaxy brains across the pond) is alpha-n.
There is also speed-density.
Not sure if there's a fancy name for maf control, not sure if anyone uses it either.

Theory

• dithering
  

need to make this clearer
Since the engine torque output is a non-linear function of many variables, and the resultant surface isn't analytically determinate, the torque surface is navigated by dithering. This involves running the engine on a dynamometer and, for each engine control variable, taking small steps in a direction and determining the effect the small step has on the torque. If the result is a decrease in torque, another direction is pursed. By chasing the direction of increasing torque for every operating condition, the engine control is optimized. this is just one big gradient ascent, but very badass.

• open v closed loop tuning
  

open loop tuning is doing it yourself, run the engine and check the outputs. closed loop tuning is usually done to a specific lambda and is handled by the ECM.

• dynamometer (should have its own page also
  

spark tuning

• mbt
  

[diagram of spark timing on torque]

fuel tuning

• duration
  
  • lbt
    
• timing
  

tuning strat for idle

Run lean, at least in the case of the 4cyls they do not seem to mind being 15+

Closed v open loop engine control

• short term factors
  
• long term factors
  
• place in motorsport
  

Data and Data Collection

• stuff needed to run the engine
  
  • cam sync
    
  • load (alpha, map, maf)
    
  • rpm
    
• stuff needed for compensations
  
  • IAT
    
  • map (for alpha-n)
    
• stuff you should get so you can figure out wth ur doing
  
  • oil pressure
    
  • coolant temp
    
• cool data so you can do custom engine stuff
  
  • cylinder pressure
    
  • knock sensor (cyl pressure can handle this if you have it
    
  • fuel flow meter
    
  • cyl temperature

I'm sure there's stuff im forgetting