More Mods...

[dieselburner]

I did some more mods to my truck this weekend. I added a couple of solenoid valves and a single pole double throw (on-off-on) switch in the cab. One solenoid is plumbed into the AFC boost sense line. I have it plumbed so that it is normally closed and will open when energiged. I did it this way so that I will (hopefully) quit breaking parts. With the solenoid valve de-energized, the engine will still develop 20 pounds of boost and get to 950 degree exhaust temperature when you floor it and hold it there. That was about what it did stock. The other solenoid is plumbed in the vacuum line that controls the front axel 4WD engagement. When this solenoid is energized, the front axel does not go into 4WD wehen I switch the transfer case to low range. This will be very handy when I am maneuvering my fifth wheel. Since I have both solenoids wired to the same switch, there is no way that I can accidentally have it in 2WD low range and have the power turned up which may lead to axel breakage. I was showing it off to my wife Sunday and when you flip the switch to "power" it REALLY throws you back in the seat if you already have your foot in it. This is one of the best mods that I have done to this truck so far. oh yeah, I mounted the switch on the backside of the plastic bezel that below the transfer case shifter.

 

[BCFAST]

LOL... . You're sick.

 

[HEMI®Dart]

dieselburner,



I like your idea of a Valet switch, on most of the time, driving to and from work. When you need the power, just turn it off. 99% of the time, I don't need the fuel either.



Before I get flamed, I understand driving like there is an egg between your foot and the accellerator is very much like a Valet switch.



See what you get for MPGs with the switch on. I wonder if they will go thru the roof? 25+?



The rocker won't get any further than the AFC Dog. The engine should run effortlessly and use very little fuel.

 

[dieselburner]

Hemi,

I have been using the valet switch all week and it is a very mod. I don't know about the deal with the guy that called it sick, but to each his own . One correction in what you said however, the solenoid is normally off and this has the afc boost line closed. I energize it to open. I have hit the button two or three times this week for a blast up the road. It does seem to be getting somewhat better mileage but it will take a few tanks to tell.



Steve

 

[HEMI®Dart]

Thanks for correcting me.



Can you post a link for the Solenoid Valve that you used.



If you remember what fittings you used, that would be good too.

 

[SlyBones]

HEMI,



You can also get a valet switch from Piers or BD. Its a kit with solenoid, tubing, wiring, swtich, etc. You only need to create your own mounting bracket for it. -- Works as described. Fits in the boost like from the manifold to the AFC.



I too drive around with it in valet mode much of the time. Gets a little better mileage but not by a lot. In general I only have my foot to the floor 10% if the time. So its only improving mileage 10% of the time. But is does make a difference.



Valet switch is a great mod.

 

[D. Showan]

How exactly does blocking the AFC boost line return you to normal boost levels? I'm not sure what you all mean. Could someone please explain. Thanks

 

[SlyBones]

When you first hit the throttle the governor lever moves until it hits the arm that sticks down from the AFC housing. Once the boost starts up, boost from the manifold pushes against the diaphram moving the arm and allowing the rack to travel further forward. Finally the arm pushes out of the way and the governor lever its the camplate. Then it follows the curve of the plate.



Blocking the boost line from the manifold to the AFC housing prevents the housing from pushing forward and moving the governor lever. At least thats the way it appears.



The actual amount of boost will vary according to how much pre-boost fueling you are using. My experience. From 0-10psi the truck pretty much drives the same. Still comes off the line decent even in valet mode. From 10-20psi now rises slowly to about 20psi. Where normally it rockets to 36 if your foots on it. Then from 20 I can get to about 30 as the rpms rise. From 20-28 its pretty much RPM boost, as it rises directly as the rpms climb. Only gets about 30 total at redline which actually takes some time. About like the truck did stock with the wastegate line pinched. -- Again this will vary from truck to truck depending on preboost fueling levels.



OK the little clause about thats the way it appears. There must be more going on here. If the AFC housing diaphram does not get boost and move. And the governor lever moves no futhter that that, how does the truck even get enough fuel to rev up, and even get to redline. While it takes longer, I get rev it up to 3000 with the valet mode on. And in general the truck drives well for daily driving. How is it getting the fuel for this level of driving?

 

[dieselburner]

I used a couple of "MAC" solenoid valves that are rated for vacuum through 120 psi that I had found. The fittings are 1/8 mpt x 3/16" barb and the hose is heavy wall vac/fuel line. I installed clamps on the boost sense line fittings.



I don't know either about exactly what is happening in the pump, I am not getting the same levels of boost in valet mode as you but I haven't had it at redline under load yet either. I get about 20 or 21 psi at 2200 rpm at full throttle. I had dialed the AFC way back (the star wheel is about half way across the opening) to control smoke at low rpm. Back when I set up the pump with the cam plate and oversize delivery valves and bigger injectors, I adjusted the afc. Also the plate is pushed back . 020" from stock to control top end temperature. It will still hit 43 pounds of boost around 1500 to 1700 rpm with the power switch on.

 

[D. Showan]

Thanks Slybones. I'm going to look over the pump and try to make sense of it