It's been a while since I've been on this board...thanks for reopening it again.
I have a ZZ4 aluminum head (street only 10:1cr) motor with a #8360 MSD distributor (light blue springs w/ 21 degree bushing), Blaster 2 coil, no box is being used, GM PERFORMANCE PARTS recommended AC DELCO MR43LTS plugs. I use TAYLOR Pro Spiral 8mm wires, 15 degrees BTDC idle timing on ported vacuum. The carburetor is a DEMON and 91 octane is used. Headers are SANDERSON QP1000 cast iron. The rear axle is a 3.42 and the transmission is a 5 speed TREMEC...all in a 3,500# '57 Chevy 150 sedan.
What is the recommended spark plug gap? Old points distributors were .035 and HEI is .045...none of my MSD material specifies a plug gap.
I've read through all of the old questions pertaining to spark plug gaps and found most had to do with using an MSD box.