afc spring????

[new dad]

is it a smart idea to remove this said spring?

[PToombs]

If you do, the cone will sit in the bottom and it will full fuel all the time. Not good if you plan on towing.

[new dad]

so as soon as i crank it up its at full fuel with the spring removed?

[ZSkibo]

You need to understand how that whole assembly works. Your fuel pin has a profile that determines the amount of fuel fed the injectors at a predetermined (by the fuel pin profile's) boost. So, as boost builds from zero it pushes the afc assembly downwards which allows the pump to feed more fuel. At max profile depth you are feeding the max amount of fuel allowed by the pin. If you remove the spring or the AFC lever you essentially have full fuel all the time AVAILABLE to the injectors. Your smoke screw is basically an adjustment which preloads the AFC to a deeper depth than stock. Following me? As you turn the smoke screw down it pushes the fuel pin downwards. Compared to stock you are starting your fuel profile at a deeper spot than before giving you more fuel prior to boost being introduced. This makes more smoke and is why everyone refers to this screw as the smoke screw.
All that said, if you remove the AFC spring you remove the boost reference for your fuel profile and transfer it to your throttle. Thus, you can give the truck as much or as little fuel as you like regardless of what the truck is doing. depending on your wants for the truck and your mods this can be a good thing or a waste of fuel. I don't run an AFC right now and the truck runs good. When I install my monster sticks next week or so, the AFC is going back in as it will be way too much fuel way too soon and will run like crap. Got it?

[new dad]

i understand. thanks very much for the info.

[new dad]

so since the spring is gone is there any reason to mess with the smoke screw?

[stoneagemaxx]

i could be corrected on this but i'd say no because your already getting full fuel off the line through the rpm range, if i'm wrong somebody7 will correct me but i'm 99% sure thats hhow it works

[ahale2772]

that correct the smoke screw will not touch the pin if the afc is at the bottom of the bore, i dont think the smoke screw will give u any more hp anyways just more smoke and more egt

[Richie O]

It depends on what injectors you are running. Stock injectors work fine with the smoke screw maxed. It helps the turbo light. If you get bigger then stock sticks then I feel it starts to hamper performance. To much fuel is as bad as not enough.

[new dad]

well the 98 3500 in my sig is fixin to be parts truck for my 90 somaybe i can make some more power here shortly. its got some goodies on it and in it lol