yup thats right i'm crazy. but I figure HEY!!! if the rustang owners get to ditch the cats.... why cant we??? I've been looking and havn't found anything close to the off-road x-pipes rustang owners get. I'm thinking this might be what my 5.4 wants. I don't know any muffler shop around here that'll do it tho. and now that they did away with the stupid e-check here I can get away with it. so what does everyone think about long tubes into an x-pipe into a small glasspack and then 40 series mufler per side then dumped with turn downs before the rear axle now how do I go about getting my dream exhaust done

 

The reason nobody has done it is because their are sensors behind the front 2 cats. I had the 2 rear cats pulled and no CEL, but you sir, will have a CEL.

 

Sounds like your going to have the cops at the end of your driveway everyday waiting for you to start your truck. lol

 

Just get you a set of 02 simulators that will solve the CEL problem.

 

What will removing the rear two cats do for the following:

Peformance? (HP, back pressure, etc.)

Emissions?

Sound?


Just never heard of doing this so I'd like to know more.

Duke

 

ive ran my past vehichles with straight hacked off cat dumps with no problem with the cops. my last car I ran a test pipe in place of the cat which was a easy bolt on mod. it sounded good but was very divable since it had a glasspack and muffler after it. my f150 also only came with 2 cats. not 4. and right now I'm runing it dumped after the y pipe (not quite as aggressive as those stupid 5.0 rustangs sound) I basically want it to sound like every mustangs worst nightmare

 

Performance, another 10+ hp has been proven. Forced induction owners are seeing [at times] 25hp improvements. Definitely no decrease.

Emissions, you will probably not pass smog.

Sound, definitely louder at idle and when lightly on the gas. Very manly now, sounds like a v8 should.

 

this is EXACTLY why I want to do this. a little more horse, alot more ***** and they did away with the emissions testing in my county YAY!!!!!

 

You better break out the flame suit.

 

why? I refuse to be satisfied with what I'm hearing from my exhaust. if the 4.6 mustangs can sound like the have ***** the 5.4 should sound like it has giant cahones. hell I've heard v6 camaros sound better than this

 

What you need to do is install a set of MIL eliminators on your rear set of oxygen sensors to stop the CEL from coming on then you can gut your cats. Another option is to use a programmer like an x-cal II to turn off the rear o2 sensors so they don't throw a CEL. If you don't and you take it in for service, the dealer will know what you did, and probably void your warranty. As far as E-check goes, only the counties in N.E. Ohio around Cleveland still have to get tested, the rest of the state is home free.

 

i'm pretty sure the dealer would know I didn't have cats just from the wonderful smell of unburnt fuel. unless they are complete morons, what would be nice is an aftermarket setup like the dynatech headers but with swappable cats/test pipe and an x-pipe instead of a y-pipe

 

Instead of wanting to sound like every Mustangs worst nightmare, why don't you do something so your truck IS every Mustangs worst nightmare? And as we all -- at least should -- know, exhaust isn't going to get your there...

There are plently of bolt on exhaust systems out there that will make your truck sound mean without all the problems of: CEL's, the awful smell of raw fuel, driveability issues, etc. If you're going for power you'd be better off bolting on one of the aftermarket catbck systems, get one of the various intake kits and a tuner. You'll have a more enjoyable truck to drive, and more HP & TQ than just hacking up the exhaust.

 

hacking up the exhaust is just one step of many.

 

I'm not trying to be a **** here, but would you care to elaborate? I just find it hard to understand what hacking up the exhaust is going to do for you. If the stock exhaust is fine for a supercharged 5.4L, then what are you going to do that'll make your truck need to flow more than a Roush blowing 7.5# down the intake?

I have the Roush "Street Legal" catback on mine. Before the Edge it was VERY mellow -- almost more quiet (at idle) than stock. With the Edge set on Level 2 the thing screams now. I can even hear it sucking in more air from the K&N 77-series CAI at idle & part throttle.

I haven't seen this debate here on f150online, but I've read it a million times on the various Mustang sites. (Most of whom think they need dual 3" pipes to flow 300hp.)