Two things

The choke and run scenario showed that it probably has a vacuum or carburetion issue.

If you have another carb, I'd swap it, even temporarily, but you could easily have a vacuum leak and cause the same issues.

Did this carb/intake combo run before the cam swap?





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- 70 Fastback Mustang, 489 cid FE, TKO-600 5 speed, 3.70 9 inch
- 71 F100 shortbed 4x4, 397 cid FE, headers, Street Dominator, 280H, 5 lug Dana 60, 4 speed