Is anyone using an MSD distributor to trigger their EST module, and if so did you have a problem getting the timing set up? I'm pretty sure my rotor phasing isn't jiving with my magnetic pickup.
I have a Caddy 472 motor, 7747 TBI from a 7.4L and a MSD distributor with the advance locked out. I have the EST module wired with the polarity correct per the Megasquirt site info. Caddy distributor spins clockwise.
I originally set the timing with the motor at TDC#1, rotor terminal pointing at #1. It would not start, backfired, etc...
Put my timing light on it, cranking the starter with the fuel pump fuse removed, and it was way off. Like 90deg clockwise on the crank kind of off.
Using the starter only, I set it to 0deg. Added fuel and it fired and ran ok. Timing light showed ECU running the timing, fluctuating around 20ish degrees.
When I tried to set the timing with the EST feedback wire unplugged, it ran but my timing light showed way off again. Weird for sure, like it's a full cylinder off in the firing order??
I have the old chevy distributor, it looks like the rotor is slightly ahead (cw) of the tower terminal when the reluctor points are lined up. I'm guessing the ECU sees the signal and then calculates timing for the next spark event.
I found out MSD makes an adjustable rotor so I ordered one. I got the adjustable rotor in today, it can go 20deg either way. I messed with it a little bit, 5deg clockwise and it seems to have a more stable idle, but the timing still does the 90ish degree jump with the EST wire unplugged. Called it a night at that point.
I can keep screwing with it, but if someone else has already dealt with this it would save me some headache. I did a search, but didn't come up with anything helpful...
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