Looked at fuel and fuel pressure is good, float bowls are good and all fuel lines are flowing. Seems like I have been having a timing problem. Replaced the Mallory unilite I had with a new MSD ready to run vacuum advance and new wires and the car runs so much better. Currently have 16 degrees initial with the stock 21 degrees mechanical. Also replaced power valve back to a 65 and changed main jets from 72 to 68 (tried 70's but still too rich). Car is running really well off throttle and midrange but is still stumbling on the higher end. I tried to give it more initial but the starter does not like anything over 16 so I was going to try the 25 degree mechanical bushing and lighter springs. Car pulls really well untill around 3500 to 3800 then starts stumbling. I have read some big block guys are running a total of 40 to 42 timing, so is it safe to go this high? Also the vacuum advance helped out a ton on normal cruising, car runs so much cooler and smoother.