I guess it all just depends on what your priorities are. I've heard from a couple people that Magnaflow delivers better performance gains than the Flowmaster muffler, but it's fair to say that you're definitely gonna get a louder exhaust note from the Flowmaster 40 Series. Personally, since I live in California and I have to keep my pre-heater and a cat. intact, I need all the help I can get with exhaust decibal levels. So I choose to run the Flowmaster. I mean, with my dual cats. I don't need to worry about having too much exhaust air flow. As far as power loss is concerned, I don't agree that you lose power with Flowmaster. While my truck has always had a FM muffler as long as I've owned it, my friend has basically the same exact truck as me. He bought it with a stock exhaust setup and chose to run the Flowmaster 40 Series muffler with dual tips. His truck sounds a lot louder and he noticed no loss of low end power, and noticed a nice little gain in the mid-upper range. He has the same setup I had when I bought my truck. Since then, I replaced my second cat. with a high-flow cat, and ran 3" piping all the back, added a new FM muffler and did away with the tips and just installed dual turndowns. I noticed no loss of low end and a noticeable gain in the mid-upper range as a result. Even with turndowns as opposed to tips to the bumper, the noise isn't nearly as bad as I would have thought. I mean unless you like your vehicles quiet, we have efi Ford trucks, not late 60's muscle cars. I don't think there's any mufflers that will alone make our exhaust tones unbearable or too loud. So yes, I'm definitely happy with the way my Flowmaster 40 Series sounds and performs. I'm not saying it's the best muffler in the world since I haven't tried them all, but I'm happy enough to stick with it. Hope this helps.

 

I'm with TF on this one.
I run two 50 series Flow masters, and i love them.

 

I just installed a magnaflow 2.5" si/so w/2.5" catback pipe and it is pretty quiet. Under WOT I mostly hear my K&N up front. But I prefer this over too loud. The guy that I got the truck from had a cheapy 'turbo' muffler with a homemade Y after the muffler into 2 rear-exit pipes with 3-4" extensions. Made so much noise I couldn't hear the radio. Fortunately for me it rusted through and my inspection was due so I bought the magnaflow. The shop had a cut-away of a flowmaster and with all those noise making baffles in there I don't see how you can gain 1 ounce of power. The magnaflow is straight through with no baffles, just perforations and glass packing to absorb the pulses. SOTP dyno and I think it runs stronger and even smoother at higher speeds than with that power robbing junk he had on there. I went with 2.5" because on my last truck I put a 3" w/flowmaster 50 and it felt like I lost a lot of bottom end. These trucks are low rpm torque producers so you can't rob the bottom or the engine is crap. I'm very happy with the magnaflow.

 

every one i know runs flowmasters that is why i was going to do it but i will check out magnaflow.

 

what is better for these truck H pipe or X pipe? i was thinking of doing a X pipe i was told that is gives better flow.

 

I was thinkin h pipe but after talkin to a muffler shop I'm goin with the x pipe if I can get it under there witha transfer case and all. The shop swears you get more from an x, but I have no personal experience with it.

 

I have an X pipe and they are better than H pipes. Look at my gallery.

 

If you put a chip in you truck do you have to run 93 octane? i thought you hade to.

 

The companies that manufacture the computer chips program them to run on "premium fuel", whatever that means. Most of the gas stations around where I live don't even have 93 octane fuel. They only go up to 91 octane.

 

my tuck is getting a AOD transmission form a 94 f-150 becouse the one that is in ther now is junk i am all most done with the job.

 

beastie how do you like you march power and amp pulleys? are the worth getting?

 

I like them alot, and for the price you really cant pas them up. You will need an impact wrench to remove the alternator pulley, but other than that they are worth it. I gained a nice increase in power, and just all around acceleration, the truck gets up and goes much better.

Also most chip companies tune for 91 ocatne not 93. My Superchip from Mike Troyer is for 91. When I get it reburned, I will probably ask for a 93 octane program.

91F-150302, in 94 the truck came with an AODE not an AOD, I dont know if your truck had an AODE or AOD, but it will make a difference, One is computer controled AODE and the other is not. However I dont know which came on your truck.

 

My truck has push button over drive and so dos the 94 F-150.

 

I dont know if that means yours has an AODE. I am not sure when they converted fro mthe AOD to the AODE. Maybe someone can shed some light on this subject for you. I would just make sure that they are the same tranny, and I dont know how to tell the difference between them.

 

what is AODE? i know what AOD is.