I had my stock muffler cut out and had a 14" magnaflow installed (used stock pipe from muffler back) on my 05 Supercrew. Truck really sounds deep and sure revs higher than before, but is alittle loud in the cab while cruising. Is there alot of differance in the overall loudness of the two? Is it worth going back and trying to somewhat exchange for the 18"?

 

18" is what comes with full cat back system and people love them. I went with the 24" and love it no drone at highway speed at all. Deep growl at wot. Hope this helps

 

If you think its too loud, its worth a try. Or you could put a resonator in front of the muffler.

 

I don't mind how loud it is when I'm getting on the throttle, but just don't like the constant resonating sound inside the cab at a constant speed. I don't think the sound coming out of the end of the tail pipe is what I'm hearing....guess it is coming thru the muffler itself more.

 

I too went with the larger magnaflow muffler (12286 -5" x 8" x 24", 2.5" SISO w/ stock pipes) on my 4.6L. Nice rumble at start-up, quiet at idle, low rumble at cruising speed (I have no tach to give rpm #) and a great sounding rumble at W.O.T..

 

I have the the 18" Magnaflow dumped on my truck and it sounds perfect. Very loud at WOT and a nice rumble when accelerating. Very quiet on the freeway. It's damn close to perfect.

 

I just had this done this morning. I also added the 35204 rolled, polished tip. Got the muffler AND the tip shipped for $103. The welding at the local midas shop was $75. I love it! No drone whatsover, it could actually be a little louder, but I think it does get a bit louder with some miles. I HIGHLY recommend this setup at $175 over a $500+ catback...same results and enough left over to get the chip / programmer.

 

Another option would be to install some sound deadening material. I just installed Hushmat on the back wall and forward to the backs of the seats (short cab), and it took away the drone, or at least made it tolerable. It is pricey, but I like the performance of my new exhaust system too much to change a thing.

 

just got my 18 inch magnaflow muffler installed today, had the shop bend me some stainless steel 2.5 inch exhaust.

alot quiter than i was hoping.

 

I have the siso with the 18". It sounds killer at all rpms in my opinion.

It does have some drone at 75mph and up but not too bad. I am very pleased overall.

 

I had the 18" 5x8x18" 12256 installed a couple of weeks ago and found it to be quieter than I had hoped for. Ther is no drone at all anywhere and I've had it up to a steady 85 on the interstate to check. The only time you hear anything at all is under acceleration, at idle or while cruising its almost stock sounding.

 

That is exactly how I would describe my setup with the 24". The main reason I went with the 24" is because enough folks were saying there was some drone with the 18", but apparently it varies. I do like mine, but if I could have it be a bit louder without picking up a drone, it would be perfect! I can't complain given that it all cost about $175 installed...much better than the $600 I planned to pay for a catback and it does growl when I get on it.

 

Same sound, sure... same HP & TQ numbers as a well designed CAT BACK....Never....thats the differance between 175.00 and 500.00...
BTW: Very nice looking mustangs...

 

That extra $325 would be a lot better spent on a programmer.

No way you'll get enough HP or torque gains (if you don't actually lose that over stock) to even be able to feel it on the butt dyno.

I'm still amazed at the price of these bolt on systems. If you figure the parts separately, some welder and tube bender are making a mint.

 

I should ad that I have the 4.6 crew. I have heard that the exhaust is louder on the 4.6 than on the 5.4. That seems odd, but maybe that is why my
18" is plenty loud. I wouldnt want it any louder. Perhaps the 24" would be best on the 4.6 and the 18" on the 5.4?

Another side note: I installed the airaid intake tube, and modified the stock airbox with the dremel to open it up a bit, with a k@n filter attached. It actually quieted the muffler drone, and made the magnaflow sound cleaner. I love the killer sound of this system. If you dont want drone though, I wouldnt recommend the 18" on the 4.6L 04 crew.