I have had my '73 Mach 1 running for almost a year now after a complete engine rebuild (351 Cleveland with vefry mild cam put in). After about 1000 miles I noticed I was getting some dieseling after turning the car off. I took it to a mechanic to reset the timing and readjust the carb (was rebuilt at the same time the engine was/original carb). He adjusted the timing he said, which fixed the deiseling but then I noticed it had a tremendous loss of power. I took it took work one night and opened it up on the highway. It was then I noticed it would start to surge really bad (almost like it was starving for gas) at around 90-100mph, which it did not do before.

I took it to an older mechanic who is regionally well known for being an excellent carb man. He said they retarded the timing too much and it was "2 teeth off" on the timing. It starts much better now, idles better, but I still notice the surging at high speeds as well as a slight hesitation when I do hard acceleration. It ahs its power back but the surging is concerning to me.

Any ideas what should be my next move?