I have a 94 F-350 XLT with a 460. The truck is registered commercially which means I dont have to smog it. I want to run true dual exhaust with an X pipe and no cats. My question is:

What do I do with my O2 sensors? will they still work with no cat? I want to take all the smog related stuff off of this engine. Will I need to reprogram the computer?

I know The smog motors lack cam timing. I also hear that swapping in a timing chain from an older 460 will help with that? Is this true?

What other smog related parts can I look at removing from this engine?

What kind of improvements am I going to notice after removal of smog equipment and the addition of headers with dual 4in exhaust all the way back?

Thanks for all of your help!

You will receive better acceleration, more power provided that you modify the intake and fuel delivery system as well, annoyed neighbors, and a mountain of noise violation tickets assuming you're running the truck without mufflers. Don't use 4 inch pipe. This isn't a diesel! If you run 4 inch with a stock intake, then your motor will run very lean, causing damage. Don't go bigger then 3 1/4" pipe. You're not building a race truck are you? You don't want to be spending extra dollars on extreme intakes and fuel upgrades that add on to the poor mileage of a 460. Not sure about the cam timing thing. That just doesn't make sense to me. I don't know what to do about the o2 sensors. Bear in mind that you still MUST pass inspection. Since that truck is 94' then I don't think that the commercial registry will save you.

I believe you can run those mil-delete thingies the sell in Jegs for Mustangs. As for the cam timing, Ford retarded it by 4 deg. back in 1972, so a '71 TC and gears will correct that problem. I don't know if they changed it since then though. 4" dual exhaust? Eeeeshhh. Good luck running that, you should have a big honkin' gas tank in the way. Not saying it's impossible. I don't think there are too many more things to really hinder the performance, after all, it does have EFI doen't it? You could always chip it too. Go to www.fordtruckenthusiasts.com , I'm sure there are a few guys who could help out there as well.

You need to check real close on the Calif. emission requirements. Here in AZ, almost EVERYTHING here gets tested, even 5 ton gravel trucks! Ca is even tougher than here.

4" exhaust?????? that would probably cost a few GRAND to have done, providing you could find exhaust manifolds or headers that can support the exit size. Thats really overkill. 2 1/2" will be fine, even on a big block.

Mark

I concur, 2 1/2" duals are more than adiquate for the job. As for the O2 sensors, if you have your current stock exhuast modified from the cats back, then you shouldnt have any problem with O2 sensor location. Other wise you are looking at drilling and welding in a bung to screw the O2 sensor into, at least the back one if your vehicle uses two sensors. You might want to check on the legality there of running dual cats, if your vehicle only has one cat, or both banks feeding into a third final cat, as is on my T-bird.
Im just glad I live in a state where we dont have to deal with politicians sticking thier noses under he hoods of our vehicles. Especially treehugging, dolphin kissing, politicians.