360 LA installing Promaxx Aluminum heads

Just checking. According to the plug your lean. Re-calibrate the 02’s. Perhaps, IDK for sure, but the placement of the 02’s might be a little far away from ideal. I use headers and there placed right in the collector, not the reducer. I also install the full exhaust system that I’ll use since it plays a big role in how the carb see’s the signal and operates.

I'm of the same mind.. looks lean to me. I'm going to get the vac gauge and timing light on it again later today... we'll see what vac and timing light say vs. the o2 sensor before the re-calibrate.