I recently purchased an 86 f250 7.5liter v8. I am trying to bring this beast up to spec. so I can pass emissions. I crawled underneath it today and noticed that the exhaust runs straight from the manifold to the muffler and no cat to be seen. I assumed some previous owner removed it/ them. Just wondering does this year and model have one or two? When I replace it/them, besides running my exhaust through it/them, what do I need to connect to, it/them? wires I mean and from where?

 

Check your underhood VECI sticker.Your truck probably did not have convertors from the factory.Heavy duty emission control vehicle.You will however have 2 pumps under the hood.

 

Your truck should have a pair of air pumps, an EGR valve, and little more. Exhaust should be 2.5" duals to the muffler, with no cats.

 

Really? thats a relief. I do have two big air pumps right up front ugly as ever but they are hooked up and appear to be functional. I was sure I was going to have to drop some bucks on new cats. Thanks for the info

 

I went through the same thing when I got my 85 F-250 with the 460. I guess the trucks with an 8500# GVW or higher dont require cats. Seeing that NON-CATALYST sticker under the hood was a big relief. One of my pumps was seized though, but it was only $40 for a reman unit. Good luck with smog, mine just passed, but only after some carb tweaking.