Help w/ rich mixture

[lopee]

So i rejeted last weekend and it runs great fron 4000 rpms and above, but boggs and is sluggish at idle to 4000 rpms.

Its a 91 w/ K&N lunchbox, Yosh TRS (welded from the collector back) and the jetting is 40/150/ 1#4 washer/ 3 turns out.

The plugs foul very quickly at idle, black and sooty in about 5 mins. So, What way do i need to turn the mix screws?  Is it out for more fuel or out for more air? seems to run better when turned out(loosened) but this doesnt help the plugs foulinng.

[lopee]

bump

[The Buddha]

OK do a float check, I know I said somehting about it when you were here ... what was it ... Just make sure both are equal and at that gasket mark +- 1mm.

But for air screws,  screw it in to make it leaner. Out for richer. Make sure your floats are OK, and then fiddle away. 3 it just a starting point. Minimal fiddling is possible, and I am surprised you're acting rich when we suddenly had a few cold mornings. Maybe you were very very rich.
Cool.
Buddha.

[ATLRIDER]

Hey Buddha,

Do the air screws only control the air/fuel mixture at idle?

[The Buddha]

Air screws or lets call them mixture screws, actually add fuel all the time. However they really control it when the butterflies are closed ... aka very low rpm, under 2000 rom and when not under load. Get this wrong and you may not ever leave your driveway. But of course you can open the throttle and rev to 4K and take off without these getting in your way, till you shut it off where it can die ...
Idle to 2K is what it works on but its also the first place of call if you are idling at 4K wehn hot and not even holding idle when cold.
Cool.
Buddha.