What is a general sign that the injectors are maxing out. i have a cheap narrow band air/fuel and don't really trust it until the wideband is installed.

Logging injector duty cycle will tell you.

If you have no way of doing that simply posting your setup along with fuel pressure and boost pressure and we'll be able to tell you if you're in the safe zone or not.

If your hitting fuel cut, they are maxed out lol jk I have a logger for a 1g if you want to hook it up and see whats goin on.

+1

And if you are tuning with a narrow band air fuel gauge you are asking for failure.

Yeah i agree the narrow bands are pretty useless...i'm running a 420a, stock rods and pistons, walbro 255, and t3/t4 hybrid on 6 psi. there is just a lack of power from 6-7k rpm or it could well jsut be me paranoid haha.

and i'm running 40lbs of fuel pressure. and i know the injectors are stock 420a ones.

I now see you don't have a 1g lol

Don't know much about the 420a engine because its a shitty engine that's not worth the time or money to modify, especially with a stock fuel system, however this could prove useful for you. http://www.dsmtuners.com/forums/420a-dsm-tech/
You need something to control your fuel like an SAFC. Just putting a wideband on isn't going to change anything, its a gauge, however a very useful gauge. Throw your narrow band away, sell it or whatever, they are useless unless you can program the voltage output of a wideband to fit the gauge.

thanks for the link

If you're on all stock fuel except the 255pump I'd keep it at 6lbs for now.

Do you have at the very least an FMU to jack up fuel pressure under boost? They are not the most ideal solution but if you're just running an upgraded fuel pump and that is it I'm sure it's going lean under boost.

First signs that you're running lean are melted electrodes on your spark plugs, white deposits on your exhaust valves, and melted pistons.

Stock injectors are not rated to handle boost to that motor, that's why a lot of the kits come with bigger injectors, FMU, ect.