I disconnected my IAC too, it helps a lot with the stability with idle AFR's. The engine will idle around 700 when cold, and around 1400 when warm, but at least it doesn't surge anymore and the AFR stays right around 13.5:1. The engine will now also start up and stay running the on the first attempt, which I was never able to do with the IAC still hooked to the stock ECU. My timing is about 8-12 degrees at the 1400 RPM idle.