I have a 93 dually with 5 spd and 3.55 rear end. This truck seems like it has always lacked power. Just recently had the fuel turned up and that helped a little but it still hard to pull loads the speed limit. Have thought of changing gears but don't know what ratio would be best. I would appreciate any help.

 

Ho turn the fuel and what was turned up? check this out and if the link don't work ..its at the the top of the page called How do i.....Check here first!! In the performance sec. lots of info there

VE pump adjustments:
http://dodgeram.org/tech/dsl/more_power/Power_ve.htm

 

Do the casual maintaince first like clean fuel filter, clean air filter etc. if you haven't already. Next have someone help you by pushing the throttle all the way to the floor with the engine OFF and see if you are getting full travel on the linkage. There is a spring on the throttle shaft lever on top of the VE pump that should break over up to 1/8 of an inch when the pedal is on the floor. Things that effect throttle travel are:

Loose or sloppy linkage componets.
Things interfering with the travel of the throttle like the fuel line that is in front of the throttle bell crank or plate on top of the pump.

IF that doesn't solve the problem pull the AFC diaphram and check for cracks and inspect the fuel pin to ensure it isn't in a bind in the hole. If either of these is preventing the fuel pin from traveling it will prevent you from getting to full fuel. A little light grease or oil will help the pin move freely.

IF all is well and the power doesn't improve you might want to put in a new lift pump or atleast check the delivery pressure.

I hope this is of some help.

 

Thanks Boatnik, you should allway start with the basic!

 

It is easy to say but sometimes hard to do.

 

Just one more thing to add: get at least a pyrometer before turning the fuel up.

 

I advanced the timing a hair on mine. I turned up the pump a hair. I put a 3" mandrel bend pipe on and I put on a 16cm turbo housing. Now I get 25 psi and plenty of power. And not too much smoke.