I just installed a 50 series SISO on a chebby. Gives me a good idea to help you guys looking for aftermarket with some tone, but not overbearing.

The 50 series has a mellow tone at idle. Its more noticable when you stand towards the rear than on the drivers side or front. It has a definative rumble past 3000RPM, under 3000 its again, very mellow. (this is coming from a guy running two 40 series originals)

Overall, I'd say those of you who want a throatier exhuas system for a small cost without a lot of drone, this is the muffler for you. If you're not dualing the pipes out, this can be done for less than $100, and sound as good as what some people pay $400 for easily.

On another note, I was over a buddies shop who was doing an F150 with dual rear exit and a magnaflow, I don't know which number it was, but it was very raspy. A higher pitched sound than the Flow 50. In my opinion, based on my reception of sound in my ear, the Flowmaster has a much deeper style tone while the magnaflow has a raspier high pitched sound.

This isn't a slam on magnaflow either, I had the two trucks right next to one another listening one, then the other, then both at once.

 

98Navi,
I was looking at putting a 50series SISO on my 03 Screw. What size pipe do you think I should use? I was wondering if 3" was ok. I'm really not looking for anymore noise, just more power and fuel economy if such a thing. I have access to a pipe bender and I can TIG weld so install isn't a problem.

dwsf150

 

Good review 98Navi!

I think alot of sound differences between Magnaflow and Flowmaster is the interior design of the mufflers. Magnaflow is straight through perforated core with glasspacking as far as I know. Flowmaster has chambers etc... to help out with sound quality. IMO, I think one is looking for mostly sound, Flowmaster is the way to go, while if your looking for performance, Magnaflow.

Here again, this is not a bash against Magnaflow just my own comparison. -op-

 

dws, I run dual 3 inch on mine, however most people think thats overkill and consider it a loss of low end torque. I hadn't noticed any loss, I have over 300lbs to the rear wheels from second one and it maintains right at 300 throughout the majority of the spectrum. As for yours, assuming your truck isn't HIGHLY modified, three inch is probably more than you need. The 2.5 should suit you just fine. (or you could keep it 2.5 to the muffler, and 3 from the muffler back) The 3 inch will increase the resonation of the sound though and make it a little louder. Mines loud as hell.

 

98Navi,
Thanks for the info. I'm not highly modified so I'll stick with the 2 1/2" pipe. Like I said I'm only trying to get a little more MPG and don't really want to hear a exhaust drone down the highway. I can only guess that the 50 gallon barrel of a stock muffler is choking the engine.