Help! I have been going crazy trying to find a suitable replacement carburetor for my 87 F250 HD 351W.

Basically, what I want to do is eliminate the two air pumps, and I have been told for many years that just taking them off without replacing the OEM carb causes the engine to run extremely rich.

Any and all help greatly appreciated here!

 

Huh
Nonsense
The airpumps put air into the exhaust, not the carb
The carb is a very nice one. I'd leave it on there and just adjust it if you think it's a little off.

 

If you get another carb, I would get a 650 or 700 CFM Holley.

 

The 625 Holley autolight is nicely sized for a mild 351.
I've only used it all up on my modded 460 in my 87 truck.
No need to upgrade unless his is bad or something.
If your elec choke and linkage and stuff still good, and it starts and runs well, and not much shaft play from being worn out; I'd leave it on there and just unhook the pumps.

 

Wow! Thanks for all the replies! The truck has 47,000 original miles on it, and it does start and run very well, but I was told that just taking the belts off the air pumps would cause a "running rich" situation.

I'll give it a shot and see what happens.

Thanks again, guys.

 

If you do that you will end up with exhaust leaks in a very short time, leaks reinstalling the belts won't fix.

Gonna remove the belts remove/plug the air system.

IIRC what can/does cause extreme rich condition, that more then jetting that just to fat to start with, is a leaky power valve.

 

Does the truck have an egr valve or a carb spacer plate with egr on it.
The only thing that will make it run rich is the lack of recirculating air after the carb (because it's tuned for that extra air)
As far as it being rich, turn the timing up a little and just see how it reacts to the extra fuel it may give it.
I just can't see it causing much issue. I'm sure the carb was tuned lean for emissions from the factory but you may experience the richer carb like some do.

In the back of the heads where the emissions crossover pipe is, you can take the crossover off and the holes in the head are tapped already. Run a chaser through it and put a bolt in it. Or you can flip the pipe around sometimes and bolt it back in place to cover the holes in head.
A little rich isn't gonna hurt anything. Just cap off the ports in the head, take off the belts to he pumps, turn timing up a hair, and run it. If its too rich you can swap the power valve or primary jets.
Let us know how it runs after

 

FYI, I've got a squarebore 650 CFM Holley Truck Avenger that's really clean, but might still need a rebuild. Barely any miles, but been on a shelf for a while. Make an offer if that's what you decide you want. I'm in Frederick, MD.