I have a full mechanical advance distributor now but was thinking about trying one with vac advance for better street manners. It would also need to be compatible with an MSD 6 box. What's out there that isn't a shiny piece of junk? Did Firecore ever get the bugs worked out with theirs? Why not use the factory electronic? That's all I've ever used with an MSD. 
'63 Dodge 330
11.19 @ 121 mph
Pump gas, n/a, through the mufflers on street tires with 3.54's. 3,600 lbs.
10.01 @ 133mph with a 250 shot of nitrous an a splash of race gas. 1.36 60 ft. 3,700 lbs.
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