I cleaned the injectors and installed new screens and seals. It helped but it still has the light stumble. I also took a look at the lower intake gaskets but they looked fine. I even pressurized the crankcase to see if they would leak but they didn't.

PSI, I know your perception is skewed, but 10 psi is a lot on a street V8. Its not an Evo :)

not really.

Doesn't really matter as the intake gaskets aren't leaking and I've never had an issue blowing them. When I was cleaning them number 8 injector was the only one that didn't have a nice stream at first. I thought it was going to have an issue only because when I changed the spark plugs a while ago cylinder 8 plug just looked a little lean compared to the others.

I know on LS motors builders will sometimes specifically compensate flow rate for cylinder 8. I think mine is 35#, while the others are 32#, something like that.

One of the PSCA guys that works on base has a turbo SIlverado. I was talking to him about tuning and he stated that when he tunes he uses high temp tape to hold thermocouples on each exhaust primary. The EGT of each cylinder is an indicator on how lean / rich it's running. He then add impedance inline with the fuel injector to balance out the flow.

Formula ford guys use a surface pyrometer and insert baffles into the plenum to balance out EGTs since with the carb motors fuel doesn't flow evenly to all four cylinders.

Get a A/I inventor and catalog that shit. I have one from Traqmate if you want to borrow it.

I finally have this issue resolved. There were two causes. The first was the wiring harness to the O2 sensors had three wires that the insulation was cracked and bare wires were touching each other and the oil pan. I called Ford to see if they still carried it but they didn't. So I tried Pick-A-Part and lucked out. Usually they only have V6 SN95 cars but this time they had two '94 5.0's so I pulled the better looking harness. The other issue was that the idle stop screw and IAC bleed screw needed to be adjusted. The car now idles at around 950rpms and no longer has the light throttle surge.

Congrats of finding the issue.

Awesome! Electrical related problems are some of the worst.

Thanks. Back when Steve tuned the car he mentioned that one of the O2 sensors was acting slow. This explains that too.