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Afc Mods

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Arrow #1 is where you want to cut material off of the afc foot. About 3/8" is what you want to take off. DO NOT cut material off of the front of the foot (Arrow #2) because it defeats the purpose of even having one in the first place.

Arrow #3 is the Aneriod Screw (Aka Smoke Screw) and allows you greater adjust ment of the afc foot. Think of the starwheel as a Fine adjustment and the Aneroid Screw as the course adjustment. Let me know if you have anyfurther questions and I would be glad to help you out.

To remove the the foot take off the AFC Housing (like you were going to adjust the fuel plate) and remover the four bolts around the Aneroid Screw. One of these bolts is a tamperproof bolt and a pliers worked just fine for me to get it out.

You can also Switch the washers around on the diaphram. There are some pics on here already.

This would be the only way I would go about modifing the Afc foot, if you were going to cut material off of the front of the foot (Arrow #2) then I would just remove the foot all together and use the skinny pedal as the pre-boost fuel control.

These modifications, plus alittle time spent adjustin the starwheel, and aneroid screw, will lead to a very good running ctd, and will allow many different levels of adjustment on how much pre-boost smoke you have. This modification will also allow full rack travel. (Assuming you still have a plate)

Hope this helps!


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very informative post. thank you. worthy of trying :thumbup:

i was of the thinking that grinding the foot [toes] is what was needed. glad to see this info :cheer:

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Guest 9812VCTD

Good info Corey I am going to try and take this same mod on myself this week.

Muddy I have heard about it done both ways but I think I will cut it the same way Corey did. Also they say to flip the washer around on the rubber diaphram.

Dumb question but how do you back the starwheel off? It looks like it is adjusted like rear drum brakes.


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Black arrow is the starwheel. Take off the cap under the red arrow with an 8mm and turn the wheel with a straight screwdriver: Towards the motor is more pre-boost fuel and away from the motor is less fuel.

From this picture we can see the gov. arm contacting the afc foot. grinding material off of the front of the foot defeats the purpose of it being there, because you can not adjust it backward agian to limit pre-boost fuel. You would be better off removing the foot completly.

Imagine a modified fuel plate in the this picture. Now, after the boost builds and the foot moves until the part that slides on the arm hits the housing and limits its movement. Then the gov. cantacts the plate and as the rpm's rise, the arm moves up. if you have an agressive enough plate, the unmodified afc arm will come into contact with the gov. arm and limit full rack travel. By cutting the 3/8 off the foot it allows the gov. arm full travel of the plate while also maintain good pre-boost charactaristics.

Clear as mud?

I hope this helps let me know if i confused the shit out of you and I will do my best to explain better


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