Ok. Ok. I asked this about my 302, then replaced that with a 94 F250, 460, E4OD, 4WD.
I got some rather confusing answers and a little bit of condescension. So I will ask again, hopefully with more thorough answers.
i want to replace my leaky exhaust. I have read that the stock manifolds flow very well. And am not strongly considering headers. Thinking of replacing everything from the manifolds back. Want to delete the entire smog pump assembly. I assume this will mean a new catalytic converter without the air pipe connection. Also I understand I will need to plug the back of the heads, run a smog pump bypass pulley, or a different belt. And will need to make a bung for my O2 sensor. So far so good.
is this doable without throwing a CEL code?
Should I run single out of the cat, or dual? I dont need a loud exhaust, and motor is fine for the power I need. I'll probably upgrade cam and timing later.
I am hoping someone else has done this by now and can give me real world answers. Not hypotheses.
If you have done this what did you use? How did you do it? Any issues?
And no, we dont have emission tests here anymore.

 

Seems to me catalysts need the air pump, they need the extra O2 feeding in to get them up to proper temperature. Otherwise, they don't work right and will probably soon clog, and in any case won't scrub the pollutants out. In other words don't bother, it's like "love & marriage" as Frank said, "Ya can't have one without the other."

 

I believe you missed the part below where he is going to replace the converter with one that doesn’t use air injection.

 

Well OK, but a 3 way cat will need OBDII and a couple different oxygen sensors to work right.

 

The PCM will most likely have to see the OEM setup. If you truly want to remove, you will need to re-burm the PCM.

 

I have no idea what that means. There is only one oxygen sensor upstream of the converter. You can remove the converter and the computer wouldn’t know. As long as the sensor is placed approximately where the factory one was located it will work fine.

 

This is the info I am looking for. Thanks for all the replies. And yes it is my understanding that if i keep the O2 sensor upstream of the cat i am fine deleting everything else. Please keep adding. Want to do it right the first time.

 

Selective hearing ...

 

Bwahahaha!

 

On a 302/351 you can remove the air injection system plumbing but leave the TAB & TAD solenoids plugged in for the computer. I am using a Mustang bypass pulley on my 302. I deleted the air system when I installed GT40 heads. I do not know what is involved in doing that to a 460.

What is leaking on your truck? Is the manifold cracked, loose bolts or broken studs? If that is all that is wrong and the air system is working I would repair what is wrong and leave it alone.

 

Here is my delete story.
I opened up the fresh air intake by getting rid of that sad little opening near the radiator cap.Think about it, a 460 trying to suck air through a hole that small. I opened up the air filter box under the filter to get more air and better air distribution through the filter. The horns in the intake tubes were already gone.

I removed everything and I mean everything except the EGR and MAP. I unplugged all of the related electric solenoids like the TAD plus whatever other thing was smog related..

I used short lengths of ? id heater hose and 1/2 inch pipe plugs on the threaded ends of the pipe going around the heads and the pipe from the cat to plug them up. The cat is going to be gutted and put back in place because I don't want to cobble together some straight pipe crap.
I will maybe positively probably maybe without a doubt get rid of the muffler and run a straight pipe because I think it may be a little plugged up.

I gutted the old crusty vacuum lines and then replaced all necessary lines with new hose and plugs where they are needed. I bought a shorter belt since the air pump is gone.I have not had an error code or check engine light.

I have 17 inches of manifold vacuum. I have the factory manuals, a breakout box and various electrical test equipment since I have a decent electronics lab.

I installed a new harmonic balancer ( major pita ) new plugs, set the timing at 10 deg btds and it runs better now than when I bought it. I think part of the rough running I used to have was due to vacuum leaks in the old lines or solenoids. And it is a torque monster now.

Did I do it the right way?? I don't know but it worked for me even though I have dain bramage.

 

Thanks for the input. This, this is the kind of knowledge I am looking for. Just want a decent running relatively clean emissions truck. That has power and torque.

 

From what I have seen that is plenty of air for the engine and it is drawing fresh cold air from the grill area. It sounds like your mod now has you using under hood air. Not better.

 

I forgot to mention the insulated box I made to take unrestricted fresh air and direct it to the filter box with a drain for rain water to escape.
It may not be pretty but it keeps the incoming air cool. I used a couple of plastic pails and a heat gun.

 

Someone replaced your I6/460 Air intake with the 5.0/5.8 intake, your 460 and the I6 comes low from the grill support(more like a Ram Air Intake), and a lot more cool air