AFC Mod Question-Less low end fuel!

Bobcat698

Bobcat698

Pure Diesel Power
This isn't your normal "afc mod" question..

When the AFC is fully slid toward the firewall, is the maximum amount of fuel reduction possible on the low end if the starwheel is tight?

I have a bit too much low end fuel with my bigger pump and I'm having problems lighting my charger. Would ADDING material to the AFC foot serve to limit fuel any more than it already does slid all the way back?

I'd like to hear some input, thanks!
(I bet Weston *Smokem* has the answer)
 
If you pulled the AFC all the way back and added material to the foot, you will loose some rack travel at WOT. What spring do you have in your AFC? A lot of guys run a 215 spring in there, takes about 35 psi to get full fuel. Oh, and Jims truck is a street truck, not a pulling truck...

Not to hi-jack, but I pulled my AFC foot out for the pull last night and sure did smoke a lot more taking off, but I almost got under the turbo. Too much fuel....
 
There are some mods that you can do to increase the travel of the afc foot. More than what meets the eye.
 
yes, you can mod the AFC for more travel, but make sure you back out the set screw on the front. this is a fine tune adjustment to allow you to set the initial travel before the lever arm hits the AFC foot.
 
Oh, and Jims truck is a street truck, not a pulling truck...
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Still works the same Bro! Enough fuel to get it going without drowning it out! You would be suprised what a little fine tuning will do. Garrett, I've already seen this on your vids, looks like your fighting blowing the fire out! Once it's up on boost that thing rocks.

Jim
 
My afc is already modified for more travel than stock, and since installing this pump I installed an "afc foot" that had not been ground on (to control more low end fuel initially), we just ground it on the backside, to allow it to go forward more.

I'll post up a video in a second.. I had a HELL of a time lighting the charger.. longer than 30 seconds. I'm sure bumping from 26 to 28 degrees played a part in it with the pump swap, but I think low end fuel control is also an issue.
 
This puzzles me.. The same day, in Helenville WI, later in the day and about 10 degrees cooler, with NO changes in the truck, the smoke looks MUCH denser on spoolup.. Does temp make that big of a difference? I mean it obviously spooled slightly easier, but wow..

Click here to see Video
 
On a big single, my experience has been that weather makes a big difference. I would see about 150rpm difference in stall speed when temp was 65F vs. 85F. Cooler, denser air is a plus.
 
Yeah, I know it makes a difference, but its crazy to see how black the smoke is on spool up and its just a gray later in the day and 10 degrees cooler..
 
Joker12valve said:
Gee what could be done about cooler air temps?????????? mabye you should up grade the intercooler. just a thought.
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Joe, its past your bed time and you have to go back towork in the morning (after being on injured-leave for 2 weeks but ended up working for me the whole time anyways):hehe:

Sounds like a good idea though on the ic ;)
 
Garrett are u to the point to where your truck is strictly a puller? If so, how bout just ditching the inter cooler all together?

I need to take some of my low end out too. Currently, the AFC is gutted so its just dumping it in there from the get go. I really wanna get it back in there and get the star wheel tightened up some to see what kind of difference it makes. May spool the charger quicker and hoping to see lower EGTs on the street.
 
Bobcat698 said:
My afc is already modified for more travel than stock, and since installing this pump I installed an "afc foot" that had not been ground on (to control more low end fuel initially), we just ground it on the backside, to allow it to go forward more.

I'll post up a video in a second.. I had a HELL of a time lighting the charger.. longer than 30 seconds. I'm sure bumping from 26 to 28 degrees played a part in it with the pump swap, but I think low end fuel control is also an issue.
Click to expand...
Looks like you need less timing or more turbo.$.02
I run no plate & do not have to wait but about 6 seconds to light at 20*
 
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DART505 said:
Looks like you need less timing or more turbo.$.02
I run no plate & do not have to wait but about 6 seconds to light at 20*
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Not arguing with you at all, don't get me wrong, but wouldn't more turbo just make the problem worse?
Also, I need to keep the timing up as need the power between 3700 & 4500 RPM.
 
Garrett, my 2cent's is that on friday it was way cooler and your smoke was black, not gray. of all the pull's i've seen of your truck i never seen it gray like that so maybe it was a coincidence or something else. was the fuel in the tank 100% the same?
 
just a thought do you run additives, I started using cenpeco pulling additive and it makes a noticeable difference in spoolup on my GT42.

Travis
 
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