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Is it safe to say that a smoke screw that is adjusted away from the diaphragm is not the optimal fueling to ignite the turbo at its earliest point.
It's different for every set up. Even the same set up in different vehicles will not have an identical, optimal pre-boost setting. Most vehicles with stock injectors/delivery valves/turbo will need some pre-boost.


In attempt to dial in my smoke screw, I assume the best method is to just lightly touch the screw to the diaphragm and then start with small 1/2 turn adjustments inward against the diaphragm?
Yes. Make sure you hold the pre-boost screw steady while tightening the nut, otherwise as you tighten the nut, it will also tighten the pre-boost screw.


Where should the starwheel tension be during smoke screw adjustment to best identify the results of tuning the smoke screw?
The star wheel adjustment does not effect pre-boost fuel settings/adjustments. They are independent of each other. If you are smoking heavily before the turbo lights, you have too much pre-boost fuel. If your turbo lights well with a haze and then begins puking smoke (considering you have no fuel plate), your afc spring does not have enough tension on it. It should either be tightened up or replaced with a stiffer (and longer) spring.
 

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More than what is typically delivered from the factory? I keep reading about the "Sweet Spot" I assume that this is not a factory setting?
I ran my stock turbo for 2 days. When I got the truck, the compressor wheel had damaged fins so I gave it to my buddy who rebuilt it. I then picked up the turbo in my sig.

With this turbo, my afc full forward, 4k gsk, no plate, TST medium afc spring and fresh 5x.010 injectors, my pre-boost screw is turned in 2 full revolutions after contacting the diaphragm. I'll add more till it starts smoking prior to spool up and then back it off a little to find that sweet spot. As of right now with the 2 full revolutions, I have no pre-boost smoke.
 

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If I had a completely stock truck, I would absolutely take the time to tune the afc.
 

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You need a longer afc spring to set up an afc properly. The stock one is only ~28mm. It will bind (WAY) before you get full travel.

The TST springs are 38mm long. They're honestly not firm enough for my application but are the correct length.

EDIT: Video I took - Here's how the heavier of the two tst springs reacts to compressed air. Like I stated, it's too softly sprung for me.

 

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I have not made modifications to increase rack travel. It will still bind?
The stock afc spring will bind because it is too short.. The bound up spring will prevent full travel.

Is the AFC not intended to recieve enough boost to make the full travel? is this why it binds?
Again, in a stock afc.. The short afc spring will prevent full travel.


Random note on afc washers: If you grind the afc washers thinner (or install thinner washers), you will 9 times out of 10 have to add more pre-boost. That's because the thinner washers are allowing the afc to return to its resting position a greater distance before the washer mods... which nets less pre-boost fuel therefore the need to add more.
 
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