anyone care to guess (or know precisely) what the ignition timing advance should be when turning over a 1600? Bearing in mind cranking RPM is approx 450 RPM....I could probably suss it out with a timing light but thought someone on here will have a figure for it... Merci mes amis
no...I got my megajolt wired up and talking to the engine last night but as the carb's off at the moment I'm just playing with the initial settings...it uses a Ford Edis as an interface for the crank sensor and the box of tricks and this should default to 10 degrees BTDC at all RPM as a limp home setting...to check that the sensor is properly lined up with the trigger wheel (ie reading 10 BTDC) you'd disconnect the Megajolt (ECU) hook up a timing light and run the engine on the Edis unit alone...any small variation can be adjusted in the Megajolt software....I figure (in the absence of new gaskets to refit the carb) If I can verify the cranking advance, I could verify the alignment of the sensor.... Failing that i can just dick about scrolling thru the various functions that look complicated and pretend to know what I'm doing.... either way, it's a novelty having my laptop in the bus
There's no cranking advance, advance doesn't come in until 2k ish, I would have to check what rpm, but it's zero advance, as in turning it over doesn't change it from stock which is generally 7.5 degrees
OK...my mistake....I'll rephrase it....given ignition timing is 7.5 degs (give or take) @ 850 RPM what would it be at 300 RPM or 450 RPM? Brain fading fast....
I wouldn't imagine there would be any additional advance. Stock, you've set your advance to say 7.5*: that's your baseline for evrything until mech advance kicks in. You need some small advance for proper ignition/combustion. So...everything below the point of mech advance kicking in will be whatever you've set static advance to.
that's how I'm figuring it, but quite a few of the megajolt vw converters are suggesting less (or more, depending how you look at it) for cranking....having said that, most of these seem to be running bigger motors, twins or throttle bodies, etc..... could also be an issue with hot starting in warmer climate....i'll try with 7.5 and see how well it fires up....*beauty of it is you can adjust via software *substitute the word 'downfall' if it all goes pear shaped
Aah, software. What could possibly go wrong ;-)? You need a modest advance to let the flamefront propagate enough, while the piston goes over TDC. 7.5* is good enough. I don't think it really matters, as long as it's some modest advance.
not particularly...it's just that some of the tuning software is open source....contributors always welcome
