Yes what they all said.
If you must drive it the way it is diaal in the timing . Start with 12 initial, all in by 3000, total of 35 with the vac can unhooked. Then hook the vac can back up and I'd use ported vac with that combo. Low compression will like more timing than that but I would start there...
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'78 Macho T/A DKM#95, 460cid, SRP pistons, KRE 310 D ports,
3" pypes, Hooker 1 3/4" headers, hydraulic roller,
10" Continental, 3.42 gears
11.5 @117.5mph 3900lbs 
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