5.7L 260h/p Alpha 1 miss.

I have an '86 Wellcraft 23 NovaXL. 5.7L 260h/p Alpha 1, TB ignition. The distributor cap had cracked. in removing the cap, the rearmost screw broke off. I had to remove the distributor assy to drill out the screw and retap the hole. In the process, broke the ignition sensor. Replace the ignition sensor, dist. rotor and cap. Reset the dist. Going off gm/mechanical experience, set the timing to 8' BTDC. Now the engine has a miss, won't run up over 3000rpm, complete lack of power. The really odd thing here is, if say the trim is all the way down and I hold the trim button down, maxing out the pump, the engine smooths out, miss goes away and jumps about 500 rpm. I have started going thru electrical system and trying to locate a short.
What is the correct timing setting?
And why would putting a load on the trim pump cause the engine to smooth out and miss to go away?
Totally baffled.

stretchmanPA. said:

I have an '86 Wellcraft 23 NovaXL. 5.7L 260h/p Alpha 1, TB ignition. The distributor cap had cracked. in removing the cap, the rearmost screw broke off. I had to remove the distributor assy to drill out the screw and retap the hole. In the process, broke the ignition sensor. Replace the ignition sensor, dist. rotor and cap. Reset the dist. Going off gm/mechanical experience, set the timing to 8' BTDC. Now the engine has a miss, won't run up over 3000rpm, complete lack of power. The really odd thing here is, if say the trim is all the way down and I hold the trim button down, maxing out the pump, the engine smooths out, miss goes away and jumps about 500 rpm. I have started going thru electrical system and trying to locate a short.
What is the correct timing setting?
And why would putting a load on the trim pump cause the engine to smooth out and miss to go away?
Totally baffled.

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Ayuh,.... My guess is, ya got a Really Bad Ground,....

I was thinking the same. I ran a ground from battery direct to block. I am thinking I have a ground issue with the outdrive. I did find the wiring to the trim limit switch (from the trim pump to the outdrive) melted. Not sure why that is. Getting to dark to work with flashlights.