FiTech EFI system

I got mine installed the other day, I replaced the dizzy as well and I still need to set the timing. While it is at an idle, it doesn't sound like it's firing on all 8, although checking the temp of the primaries they all we're the same temp so I think it's loading up. While it was idling it only took about 30 seconds until my eyes were burning so bad I had to shut it off. The A/F read correctly, my thoughts are I have an exhaust leak and it's sucking in some air, causing the computer to throw more fuel at it. Does this sound possible?