My friend is working on a 86 F250 with a 351W for someone he knows.

Instead of the usual type smog equipment I am used too. It has 2 smog pumps, and no cat.

What is the advantage of this set-up if anything or was it just a different way of doing things?

 

The label on the radiator support under the hood would say NON-CATALYST if it came that way from the factory.

Here is mine for reference:



Certain heavier-GVWR trucks were built that way although I'm used to two smog pumps on 460s, not Wheezers.

 

How common was it? I never heard of anything like it till I seen that truck.

 

Well, like I said earlier, I'm used to seeing two AIR (smog) pumps on 460s, I think this is the first time I've heard of a factory installation on a Wheezer.

IIRC the 460 was available only on the heavier-GVWR vehicles, of which comparatively few were made. Those trucks had different Emissions standards as dictated by the EPA, therein lies the explanation for not catalytic converters on such trucks. I think it's over 9,000 lbs. GVWR but don't remember for certain.

Are you sure this engine is a Wheezer?

 

Yes, and it is stickered as such.