Put a new motor in the boat swapped ot the 1985 350 for a Vortec 350. Also installed a MSD distributor and 6m-2 ignition and a clay cam. I am wondering what to time this thing at? I got it running and I can not get the base timing any lower than 12degrees without the motor stalling out. Could the cam timing be off in the motor? I also have the carb idle screw all the way in adjusted almost to the max. I checked for intake leaks. none are present. I am thinking the cam chain could possibly be off. Or could i need a advance timing light to set the total advance to 36 or so to see where it is at? thanks for help

What size cam? Are you still using the Merc TB ignition advance module. V8's are 22* or 24*. Was the cam degreed in when installed?

I am also running a MSD Dist, 6AL, B3 coil with a 22*TBIV module. It's very easy to set the timing. Get 14* base and while engine is running rev manually off carb to 3000-3500 rpms and confirm full advance. With a 22* module and 14* base I run 36*.

A Vortec engine does not run that much advance. 30-32 degrees total advance would be about the most to run.

some timing lights don't like an MSD trigger, you could be off 20* and not know it

I'm not sure of the lift on the cam. When playing around with the timing i can make it run pretty good at idle but the timing light shows the pickup line on the balancer on the other side from where the timing marks are. timing marker is at say 1oclock and the damper line is at 11 oclock I am ready to check the cam timing