Melovidov21, come join all us in the pre 97 section!!!

 

I'm sure that would drastically improve the sound, but I'm afraid with the emissions testing they're doing in Texas now when you get your truck inspected that it wouldn't pass. You're right though...the sensor is BEFORE the cat.

 

I have the Flowmaster 50 now with stock exhaust. It's not loud enough. That's why I'm going for the 40.

 

OK, Superduty exhaust consists of:
2 O2 sensors, one in each manifold before the y pipe
1 y pipe, very constrictive
1 catylitic convertor
1 muffler
3" pipe from the y pipe down to the tail pipe
That being said, I have tried Straight piping my Gibson cat back to get more sound. Not quite right. I listened to the exhaust without a cat back, still very quiet. My Gibson is a SI/SO with a 3.5" SS tip.
IMHO, cat backs just don't cut it. For what I was looking for, and the money I spent, the results were very disappointing.
12th man, here's what I plan on doing.
High flow y pipe
High flow cat
Either Gibson, Magnaflow or straight pipe
A high flow cat should be between 100 - 130 bucks.
Anywho, if you're looking for maximum sound, that cat is killin' ya. Straight pipe was cool for a few weeks. But it wasn't deep or aggressive enough. If I ever get around to it, I'll finish my exhaust.
BTW, I don't mean to **** people off who like cat backs. It works perfectly for some. It just seemed like a dull knife, it just ain't cuttin'.
12th dude, please post your esults, I would like to know your opinion on the FM40

 

I'll definitely post my results. Right now I'm looking at getting the FM40 with dual 3.5" tips. However, at the recommendation of the installer, I'm also considering the Flo-Pro "Twister". This one apparently sounds similar to the Flowmaster but is about $50 cheaper and supposedly offers better performance than the FM. If a high-flow cat only costs $100-$130, I may get one of those too....

 

http://www.cgsmotorsports.com/mufflers.htm

 

Here's what I did:
http://members.shaw.ca/pferlow/exhaust_f-150.htm

If you do have any exhaust sound clips please send them to Kelly on www.fordf150.net and he will post them on the site for everyone to listen.
http://www.fordf150.net/board/viewto...=1200&forum=16

Clips are posted here:
http://www.fordf150.net/photopost/sh...at=512&thumb=1

A straight pipe in place of the muffler doesn't sound low enough, that's what a magnaflow or dynomax ultra-flo will correct. The large chamber of their straight-through mufflers create the low resonance you're probably looking for.

 

Okay...I took my Superduty in yesterday and had the cat back installed. I got the Flowmaster 40 Series, 3" SI, 2-1/4" DO. I ran the pipes out the back and put long 3-1/2" stainless steel tips on it. I just flat out LOVE the sound. It sounds VERY good, whether you're just idling, revving the engine, or under acceleration. I was afraid that it would never sound the way I wanted it to because of that big cat, but it sounds just like I wanted. It's got a very powerful and aggressive deep throaty sound under acceleration and a nice, deep rumble sound while just idling. I really like it a lot and highly recommend this setup for anyone else out there with a 5.4L in a Superduty.

For anyone in the Dallas area looking for a quality muffler shop, I was VERY impressed with the knowledge and quality work of the folks at The Best Little Muffler Shop in Texas. They did really good quality work and didn't mind that I wanted to watch. They used 14 gauge stainless pipe, put my tips up high and tight against the bumper like I wanted, and just overall did a very good job. On top of that, they agreed to do whatever I wanted to get it to MY standards. Very nice folks....

 

You said earlier that you used to have what sounded like an exhaust leak, but you know that isn't the case, is it still there after you put your exhaust on? I am wondering because I think I know the sound and my f150 does it too, it might be normal. I have the exact same exhaust set up that you do on my 5.4 and love it, but that sound bugs me. It seems to come from under the driver's side...

 

oh yeah, for anyone in Austin TX, Leonard's Garage on 183 was a great place to get an exhaust too they put it close against the bumper and did a really good job making it look like I wanted it to look like.

 

What you describe sounds like the same sound I have...and it's probably still there...but if so the new cat back drowns it out.

What I have/had sounded like it was coming from the driver's side too...right behind the front wheel. I know it's not an exhaust leak...and I really only heard it under accleration...but now when I accelerate all I hear is that Flowmaster with those long 3/5" tips. I'm a happy camper.