The plugs hadn't been pulled since they were installed a few months back. Same plugs were in the engine when running on the engine stand. Couple hundred miles on the plugs now.

The previous 15 minutes prior to them being pulled for the compression test and picture is about ten or so minutes of 2,900-3,000rpm steady state on the highway at 18:1 AFR and ~42 of timing, then a few minutes of idle while I shot the EGT numbers with the temp gun. I idle it at 13.8:1 AFR as it provides the stablest idle at 650rpm. Timing was around 10-12 but wobbles a bit at idle as the Megasquirt is using timing to control idle speed since I don't have an IAC.

(On my Buick I run a static timing number during idle and may do so here if I get an IAC on it, and my Buick also idles around 15:1 as richening it up doesn't seem to smooth out the idle any on that engine)
Rebuilding an OHC Pontiac 250 with EFI and a Turbo