I have a 2005 F150 with the 4.6L and right now I am running an IMCO Extreme 1 chamber muffler with a 3 inch pipe. I want to replace this muffler with something quieter and more performance-oriented. I am looking into Magnaflow and Flow Pro mufflers. I am leaning towards the Magnaflow. I am planning on dumping the exhaust right after the muffler. Will this cause a loss in torque or will it be sufficient due to the Magnaflow's straight-through design? I understand on baffled mufflers like a Flowmaster this results in a torque loss, as this occured when I had a dumped 40 Series. Second, how loud is the Magnaflow muffler? I am looking at the 5x8x18 that comes with the catback kits and seems to be the muffler of choice for trucks. Third question, should I run a 2.5 inch or 3 inch muffler? I have a 3 inch pipe welded to the 2.5 inch right where the stock muffler bolted in. Should this be replaced with a 2.5 inch to the muffler or should I run a 3 inch muffler from there out? Thanks for your help.

 

just buy the magnaflow kit under $400 shipped you can't go wrong with ss pipes full 3" and made to fit your truck. sell your exhaust you have on their now and your good to go.

 

I don't want pipe, just the dump.

 

It has been my personal experience with dumps that it is not a good idea. I'm sure you know this already, but it will not make your muffler any louder. it will just sound louder because the exhaust note is resonating underneath the pick-up bed, and the end of the exhaust system (the dumps) will be closer to your head so you hear it more.

I hated my dumps on my 96 f-150 351 v-8. It always smelled like exhaust inside the truck and made me sick to my stomach. I prefer the sound a good pipe and exhaust tip add to an exhaust system. I think it rumbles more when it resonates through a big diameter pipe and tip.

just my opinion

 

Dar-Dar, the first muffler I had on this truck was a 40 Series Flowmaster dumped before the rear axle. The sound was pretty decent and the volume wasn't bad either. It sounds like your 1996 had some serious exhaust leak because I couldn't smell exhaust at any time in my truck or outside. I like the clean look of no exhaust pipes. I do have 1 tip coming out at the stock location and while I like it, I think that it looks better without pipes. Furthermore, the dumped exhaust eliminates all the bends necessary for piping to go over the axle, and this helps the exhaust flow a lot.

 

I had a dumped magnaflow on my old dodge dakota r/t with the 5.9L. It sounded pretty good but wasn't loud enough for me so I changed it out. Why are you changing out the IMCO on your truck now? BTW, by the time I sold my dodge I had about 10-12k in the motor and exhaust. I had tried just about every muffler and exhaust setup available and wasn't very impressed with the magnaflow. Wasn't loud at all and didn't notice a performance increase over stock. (Not intended as a flame towards the magnaflow fans here)

 

05STX, I am changing it because my IMCO is way too loud. On the freeway I can't even talk on my phone because I can't hear the other person due to the drone. I am going with Magnaflow because in my experience on every vehicle I have driven before and afterward, the Magnaflow made an immediate difference. The biggest difference was on my girlfriend's 2002 F150. She had a Flowmaster 50 Series the previous owner put on and wanted a better sound. After the swap the low end of the truck is much improved and she gets better gas mileage. My cousin bought a 2006 F150 4x4 with the 4.6L and replaced his stock muffler with the short 14" Magnaflow. It sounds great, very deep and smooth, and the truck is peppier off the line already. Stock he could not spin his tires from a stop but he can now between the intake silencer removal I did last night and the Magnaflow today. Clearly, by looking at the highest quality performance brands (Banks, Borla, Bassani, etc.) they all use a straight-through perforated tube design. The same is true of the Magnaflow, and this promises better performance than any baffled muffler.

 

fourpointsix, so you have actually heard one of these trucks w/ the 14" magna on it? What do you describe the sound like or as being comparable to? What would you rate it on that scale from 1-10 I asked you about last week as far as sound quality and volume? How does it sound compared to the flow 40 you had and the imco?

Didn't you say you're getting the magnaflow thurs., which is today......(when I get up it will be anyway)?

 

Higdogg, I have all the answers you need. I just had the 18" Magnaflow put on my truck this morning and I love it. I'm sorry I wasn't able to get a video of the IMCO up. My friend has a very nice digital camera and as we prepared to shoot video last night, we found out it is damaged. It must have occurred during his last move 2 weeks ago, and it is understating by saying that he is furious.

First, I will talk about these trucks and what I have learned today. I went to a different muffler shop from my normal one and the owner explained to me the 5.4L is a much quieter engine than the 4.6L in all applications. This will explain the discrepancy between the loudness of my vehicle compared to mattadams' truck with the 5.4L.

Secondly, regarding Magnaflows in general. Higdogg, I agree with you 100% that the Magnaflow is the best sounding muffler for these trucks. It is the deepest sounding muffler I have heard, and it is extremely smooth throughout the RPM range.

I had the opportunity to hear the IMCO and Magnaflow side-by-side last night. My cousin just purchased a 2006 F150 4x4 with the 4.6L engine. He put the short 14" Magnaflow on his truck in the stock pipe with a 3.5x18 inch angle cut tip. We had two friends drive our trucks and do runs down the street one after the other. They would drive easy, moderate and WOT back and forth so we could compare the sounds of the two mufflers. While the IMCO is definitely louder, the 14" Magnaflow is ALMOST as loud, and is deeper and smoother by quite a bit. I must say it embarassed the IMCO. On a 4.6L, the 14" Magnaflow is louder than a 40 Series Flowmaster.

Today I had the 18" Magnaflow installed on my truck. I had it dumped before the rear axle. It sounds just as deep as the 14", but the volume is lower. With the 14" there is a reasonable drone on the highway w/ 3.55 gears at 65-70. With my 18" there is literally 0 drone. As far as power goes, my truck is the most responsive it has ever been, with the Flowmaster being the weakest and the IMCO being alright. I will now rate all the mufflers 1-10 with 10 being the best so that everyone on here can learn from my 3 exhaust experience and only buy 1!

Flowmaster 40 Series (dumped)

Volume: 7
Sound Quality: 7
Performance: Lost low end

IMCO Extreme 1-chamber (3" tailpipe)

Volume: 10
Sound Quality: 8
Performance: Better than the Flowmaster, still some low end loss from stock

Magnaflow 14" (2.5 inch tailpipe)

Volume: 8.5
Sound Quality: 10
Performance: Better than stock

Magnaflow 18" (3 inch dump)

Volume: 6
Sound Quality: 10
Performance: Better than stock

Moral of the story is: When people on here recomend Magnaflow they aren't kidding! I'm sold on these mufflers. It's a straight pipe with insulation. It doesn't get better than that!

 

wow, very well done fourpointsix. i would tell u to get a life, but i was standing right there with u!

 

What's up Geoff. We need to get some pics of your ride up. And set up your signature!

For those viewing - Geoff is the cousin I was talking about.

 

fourpointsix,

much thanks man, that was the best exhaust post I've ever read on here and I wish it was posted all over the 2004-06 page. Everyone needs to read it. For once, someone (you) posted something about exhaust that makes sense, is easy to understand, compares several products at the same time, and on top of everything else it is factual information and not just the opinion of someone who knows nothing about exhaust or exhaust sound like a majority of the posts are.

I really believe you like about the same exhaust tones as me, so I can trust your info 100%. I'll probably look into getting a magnaflow 14" now. I've always liked the smooth sound represented on their web site, but everyone on here always said that it was a quieter muffler than the rest so I shied away. Volume of "8" is about perfect for me. What is the deal w/ the drone on the 14"? Got any idea why? The 18" at your volume rating of 5 is a little quieter than what I want right now. Why did you decide to go that route instead of the 14"? Is the drone going to be annoying w/ the 14"? I can stand a little drone, I don't think my truck really has much tone to it at all at 65-70 mph, that is cruising speed for me, I barely have to touch the gas. Mine is mainly 35-50 mph. 3.55 gears.

Okay, so the imco must be a 'rougher' sounding muffler from the magnaflow, right? Is that necessarily a bad thing? Probably more growly or something. What if the imco was a volume 7 or 8, would you have kept it then? Since you said it is quieter on a 5.4, I am still considering it. What would you guess the volume of the imco to be on a 5.4?

What was the explanation at the exhaust shop for why the 5.4 is supposedly a quieter engine than the 4.6? I don't understand that. And finally, how much was your magnaflow 18? I might search for the 14" online and order one in the near future, aluminum of course. Did you get the aluminum one? Overall, w/ your experienced opinion, do you think I'd be happy w/ any of the magnaflows, 14 or 18? Thanks again for all your informative posts.

 

geoff and fourpointsix,

I'm going to be in cali next week for my job, but only in the san diego area monday and then in the LA area until friday. Wish you guys were closer to that area so we could meet up and I could hear your trucks. If I'm not mistaken, you guys are a good drive away from LA.

 

Higdogg, I was hoping that post would be helpful! I wanted to steer you to Magnaflows because they are the best sounding mufflers out there. And the performance factor is not to be ignored. In any situation the straight through design of the Magnaflow will outflow baffled designs.

As far as the case size - the 14" is pretty droney on my cousin's truck cruising around city streets but on the highway it is only a slight drone. It is definitely pretty loud. I was expecting it to be quieter than the 40 Series Flowmaster but it's definitely a lot louder, but at the same time more refined. However, since you have the 5.4L I am guessing it will be a bit quieter. I am estimating that in volume terms, the 5.4L is about 1-1.5 quieter than the 4.6L. So for your truck, the 14" Magnaflow would be around a 7, which is probably ideal for you. I got the 18" because I ended up dumping my exhaust under the bed for the clean 'no pipes' look. After driving my cousin's truck the night before I decided the 14" would be too loud dumped, and I was correct. The 18" is still quite loud around town. The only difference is slightly less volume and a lot less drone than the 14". The deepness and sound quality are identical. I wouldn't be afraid of the short muffler since the 5.4L is a quieter engine in general.

Are you planning on a SI/DO setup or will SI/SO work? It cost my cousin $130 for the 14" Magnaflow welded into his stock pipe and a 3.5x18 inch angle cut tip. Note that if you want it in the stock pipes, the Magnaflow to order has offset/offset configuration. It cost me $125 for the dumped Magnaflow. The cost was slightly higher because of the 3" diameter. There is an upcharge over 2.5". You can find the mufflers online at hottexhaust.com or performance-curve.com for about $60, so $70 shipped.

LA is about 6 hours from where we live unfortunately. If you could swing by the Bay Area at any point in time we'd gladly meet up with you. Hell, if you come up here I'll let you drive my truck.

 

I forgot to mention also I might have to change the 18" volume rating to 6. It's louder than I thought! Just about perfect.