Ok put new set of gt40 heads on my car after breaking oil pump shaft, old heads valve spring retainer desinagrated locked up pump. So replaced with gt40 heads mild port and roller rockers.removed distributor of corse, re installed it now car is popping back thru exhaust and has no power buddy of mine is doing work he says its the injectors,but they were fine before. Is this a timing issue sure seems like it to me,but hes supposed to be the mechanic. Any ideas on what it might be???????? He said thers a couple ways to set timing???????