I was sitting around on night shifts thinking of a way to turn down my truck and to get better round town & highway fuel milage.

Normaly people use a valet switch but with my small pump and injectors I knew I would have to set my AFC foot way forward to get any power. This would make things way to smokey down low in the boost/ power band. Since that would be going against the economy I was looking for I came up with someting different. It's not rocket sience but it works..at least ok.

I wanted to use a regulator to limit the boost pressure to the AFC but did not have one. I did have some needle valves so I gave those a try. I ran a new line from the intake manifold to the cab, put a needle valve under the dash by the hood release ran the line back through the fire wall put a tee in line with a nother needle valve off it to atmosphere and continued the line up to the AFC. The Idea is to be able to pinch back air flow/ pressure to the Afc so It does not travel forward very fast and hopefully not all the way, just enough to get good power.

First I set the AFC up so I don't have any smoke off idle, a little less than half way forward on my truck (I had increased the forward and back travel of the Afc foot before hand) then started to play with the valves and the star wheel.

There is a lot of varibles the consider like:
-The position of the Afc foot at 0# of boost, (instant power availble all the time)

-How tight the star wheel is set (rate Afc moves forward under boost)

-How much air flow is allowed to the Afc through the in line needle valve (full valet mode...full fuel {normal} and hopefully something in between)

-How much air is vented out to atmosphere through the vent needle valve. (This ended up being the fine tune on the rate the Afc moved forward as well was used to limit the travel of the Afc foot {by limiting the amount of boost that built up in the line} )

All of these things work with and against each other and after 5 hours of testing I got her set up how I like. It was hard to get good controll on how far the Afc foot moved forwards. It was also hard to get it to both fuel like normal and fuel just enough in semi valet mode by only adjusting the in line needle valve in the cab.

It ended up that the star wheel was just slightly looser than normal. The vent to atmosphere is open 1/4 turn and the in cab valve is very touchy to get set up right in semi valet mode, 1/ 16 of a turn can make or break what you are after.

I dont think I would recomend this to someone that dosen't have full understanding of how the Afc works. Being able to tinker with valves for 5 hours helps too.

In the end I have full fuel like normal and with a little trial and error I can get about stock power dialed in. I can also go to full valet but for my set up I can only get about 55 mph in.. ohh about 20 seconds out of it.

I am going to look for a good regulator that is not to bulky and put it in the cab. I dont know how much restiction they have, might have to put a bypass around it when going for full fuel. Me thinks a good regulator would work about 100x better.

 

thats a wicked idea, i wish i had thought of that a while back! Get a Paton on that! i hate it for ya if someone turns them tho!

 

Very Interesting

to say the least..

Rick

 

That's on my list for this week.. I had been thinkin of the same thing before. just need some fittings and the time, already got the regulator...

This will look like a in cab TST 6 position Ford chip

turn it right for more power and left for less and valet