ofcmarc

Could someone please explain the difference between what exactly the Smoke screw and the Star Wheel do to effect how much fuel and when?

The both change the preload on the AFC correct?

I'm still playing with my settings. It's close to perfect but maybe I can get it even better....

taterfarm

smoke screw - amount of fuel at no boost
star wheel - amount of fuel with boost

the smoke screw is touching the fuel pin when there is no boost. if you turn it in(clockwise) it pushes the fuel pin down, that gives it more fuel ( fuel pin has cone on end)

the star wheel if for when there is boost to push the fuel pin down off the smoke screw. the further in the star wheel is (clockwise) there is less tension on the spring requiring less boost to move the fuel pin. with the star wheel in you get more fuel faster with boost.

So

too much black smoke with no boost go up with smoke screw(ccw)
want more black smoke with no boost go down with smoke screw(cw)

too much black smoke with boost go up with starwheel(ccw)
want more black smoke with boost go down with starwheel(cw)

ofcmarc

Thanks Tater. That's kinda what I was thinking and what Iwas basing my tunning on.

Always good to double check yourself.

PapeCAT

My preference is to back the smoke screw all the way out, have the stock fuel pin at deepest setting, remove the high idle screw, and remove the starwheel altogether leaving just the spring (acts like the starwheel at bottom + a lil more)
I leave the fuel screw at 10% above stock that makes 32psi boost clear no smoke at wot

Ace

It must smoke like a tire fire going up through the gears.

wannadiesel

Not quite, but from the rest of the post I can see you've got a good practical handle on pump tuning. The position of the AFC cone controls the amount of fuel you can get when there is boost. The star wheel has no effect on the amount of fuel available at full boost (unless you run it up so far you get coil bind and limit the AFC cone travel). The star wheel setting adjusts how much boost is required to get full fuel.

taterfarm

Thank you for clearing that up. that makes sense now.