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Hi All,

Got a bit of a weird request from a friend who I'm converting from $11 to 12P.

He wants me to increase how long the engine cranks before firing, he did have a specific reason for it but for the life of me I can't remember why (He was an old school carby guy who is used to cranking engines to "build oil pressure" before they fired, he gets paranoid about how quickly an EFI car fires which is an argument for me to have on another day).

I've tried increasing the 'Number of reference pulses to allow fuel run mode' and 'Number of successful references to allow eng run' however this hasn't made any impact.

Any ideas?

Thanks in advance!

How many pulses did you add?

For the V8 motor there would be 4 pulses per revolution of the motor or 8 pulses for a complete 8 cylinder cycle (2 full engine crank rotations).

immortality wrote:How many pulses did you add?

For the V8 motor there would be 4 pulses per revolution of the motor or 8 pulses for a complete 8 cylinder cycle (2 full engine crank rotations).

I tried up to 150 and cranking time was still approx 1.5 seconds from cold start.

I think that is likely affecting fuel run mode, which means it would stay on cranking fuel longer, which means it'd still fire and you may not notice the difference. Its also not going to provide what your looking for. There is no option to provide a delay like you are asking. From the moment you key on you have cranking fuel and module spark, and switch over to ECM control happens on RPM. You could raise the RPM, but I dont think it'll provide a noticeable delay, and if you go to high on the RPM it might not start at all as it'll stay at cranking stage.

Maybe he could add an extra guarded momentary switch which goes to the starter solenoid while the key is in "ACC". If the ignition & ECu aren't powered it would turn over but not fire.

If dude wants oil pressure before start, a simple hobbs switch should work fine.