Tuning with jets, Power valves and an O2 guage

I agree. There is something screwed up inside. I don't know what the hell happened. Either something slowly degraded or I messed it up when I changed jets and the PV. Bad gasket blocking a passage?
I changed the cam to avoid detonation and now it is worse.
I blame no one. This is a tuning issue. The '509 cam was too small for the engine anyway. I have wanted an excuse to try a different cam for a couple of years.
Its hard to know if the 850 was slowly getting worse when I had the 509 cam. It was getting worse and was pinging more.
Months ago I talked with Dwayne Porter. He thought the car could be made to run better with some tuning. I should have listened and installed this wideband A/F guage back then.

After looking at that Holley 870 carb on the Summit site, I looked at the 950 carburetors. CRAP those are expensive! The Summit racing CFM calculator shows this: 493 engine with a 6200 rpm max needs 751 CFM for a street car and 972 cfm for a strip car. Maybe the 870 would be a good choice since I don't plan to race the car. If ever, I may make a few passes to get an idea of the cars potential.