LOP223

I was wondering if the fuel plate is full forward, as mine is, can the AFC interfere with arm going out to the plate? I dont have much smoke at high throttle and rpm, just haze. At low throttle and boost I have black smoke. I'd like to reduce the low demand smoke and play with the high demand to fine tune it. The turbo is at stock boost(30-32 lbs, so far). The fuel plate is full forward, and I adjusted the afc housing full rearward. Would tightening the starwheel be the next step?

Tate

Your plate can interfere with the AFC moving forward far enough. Chances are is it just doesn't have enough stroke as it is right now, and is limiting rack travel. You could pull your plate out and it would likely be very similar if the AFC travel is limited. Read up on AFC mods to increase travel. If you want to cut your low boost smoke, slide the housing back a bit. That will reduce zero boost smoke. Increasing the preload/spring rate will reduce smoke during low and medium boost.

LOP223

I moved the AFC housing full rearward, but still have decent amount of smoke when lightly accelerating through the gears. When at full load I only have a grey haze. Seems too rich pre-boost and maybe ok or lean at full load. This is a new engine (for me). Was rebuilt due to cracked pistons. Had found the plate was full forward with no pyrometer. Its possible the AFC has also been modified. I will look at the AFC spring and see if it has any tension or backed off. Is there a good way of testing when the AFC moves without removing it and bench testing?

LOP223

I found the AFC starwheel had been completely loosened, which explains the smoke. After a few attempts, I adjusted the starwheel and now the low end smoke is gone. The first try was way too tight, no fuel till about ten lbs of boost. Backed it off and found the happy medium.