After thinking about it, I think I'll ask the muffler shop to install an O2 sensor when I take it in for some work sometime this summer. I can run a multi-meter on it. In the meantime, I'm going to continue the shot-gun tuning approach.
My primary jets are stock 51. Gbauer's got 52's. My larger valves seem to be a bit thirstier than his, so maybe I'll try 53 next.
For the Power Valve, my understanding is that the rating is for the point at which the vacuum needs to drop to open and not for the amount of fuel that comes out, correct? The summitracing tuning video says there are two ways to think about power valve size selection. First is the same as Holley, take the vacuum at idle in gear, divide by two. Second is to take the vacuum and subtract two. My idle vacuum is 13 PSI, meaning 6.5 (came stock in the carb). My vacuum at full throttle was something like 2 PSI, measured before I adjusted the secondaries. I had put in 8.5 which had shown a marked improvement. I've got a 9.5 on the bench. The engine seems to run so well at upper RPMs (assume with secondary's open) that I don't want to touch anything more on the secondary's.
How much risk to bump to 53's and 9.5 power valve?
