Quote:
Originally Posted by justjohn
This is cool. How did you do it? Would it be possible to set it so that it does it in 5th gear only so it wouldn't hamper actual engine braking?
|
I use megasquirt fuel injection which has several additional outputs that can be triggered by any number of parameters or combination of 2 parameters. The car came with a solenoid valve that feeds vacuum to the EGR in order to open. At first I played around with trying to eek out some FE under load by turning on EGR under specific situations but looking at my data logs, injector pulse width actually increased when EGR was on to maintain the same RPM at the same load. The only benefit i noticed is that the car coasts further on over run. So now the EGR is turned on only when TPS is at 0% (closed) AND RPM > 1500. All other situations EGR is OFF.
I haven't thought about limiting it to a specific gear. I would need to add an additional input to tell megasquirt what gear I'm in. Another option would be to turn the idle control valve to 100% duty cycle (wide open) when the TPS is closed but again, I have't tried it yet. The EGR is easier to trigger.