Replaced the FM series 50 with a series 40 delta flow.

Tail pipe rusted/fell off the FM50 muffler after 2.5 years--- THAT sounded good too

MPG went from mid 13s to 15+/- since. FYI... (last 7 fill-ups anyway --- no change in driving habits --- if anything heavier foot)

Not to mention the SOUND.... man.... what a difference.

I get more people telling me that "damn.... that sounds nasty" ...

 

Kraut, I'm looking at a Flowmaster muffler/tailpipe set-up for my '02 5.4, want a nice rumble, but not ridiculous, and of course I would like to pick up 1 MPG...would you recommend the series 50 or Delta? Should I go with the 3" in, 3" out kit? Is the muffler bolt on, or does it need to be heated up and slip fitted?

Thanks

 

I had a 50.. it had a good note, but was low on the noise meter.

I, personally, recommend a delta flow (series 40).

I believe it is (in my case) 3" in / 3" out, utilizing the stock tail pipe/inlet pipe assembly.

The delta is noticably louder than the 50, but, imho, NOT obnoxious. It has a good rumble, sounds great, is loud enough for someone to realize that "something's up" beyond stock. Interior noise with the delta (resonance of the exhaust note) is noticable, but, again, imho, NOT overtly obnoxious. Again, this is all a personal sensitivity matter. A motor head at work would like it louder. Another guy said: too much for my taste. I think it's just right.

I recommend finding a good muffler shop to install. I didn't watch all that was going on, but torches were used, thus I believe a slip fit was employed on the discharge side which was welded.

On the inlet side, it was slipped on with heat and is held/sealed by a mechanical clamp set-up.

Realize: the stock tail pipe is stainless, as is the FM. Thus, don't let them sell you a new tail pipe, unless you're hell bent on running the pipe elsewhere from the stock setup.

Istalled Pirce (SE Ohio): $150

Hope this helps.

 

paddy, if you're e-mail functionality is enabled, I'm willing to send digipics if it helps you to see how it was done.

BTW, keep an eye open, FMs ARE directional ...

Had the shop (when I put the 50 on) try to put it on backwards (???)

 

I just put on a FM 40 single in dual out on my '05 F250 SD. i love the sound of it. The only thing is i noticed that it seam to have a hard time shifting or down shifts. not to sure if its because of the new exaust. Do i need to make any changes to the computer? or will it change and set its self?