Big Miss

I have had a intermittant miss for a while now. It happens under load 4th or 5th gear, around 1500-2000 rpm. I have done a full tune up, and get no codes other than 44, thermactor fault. I have done KOEO KOER and the cylender ballence test. Nothing.
I have changed out the TPS, O2, plugs, wires, cap, rotor, coil, TFI module, retarded the timing, fuel filter, I have good fp at idle, timing is around 14, It likes more but I have backed it off a little. What else can I try?
I have a stock 86 block and heads.
Shorty equal length headers, catback exhaust, 3.55, some type of chip (Dont know did not install it).

plugs are gapped at .054, I think that is stock. Yes they are longer than the plugs for the e7 heads. I have not pulled them to check their color recently.