Each person has their own taste as to what is loud and what is not. I was told that the flowmaster 40 series was going to be alot louder than I wanted. I went ahead and went with it and I think by the time it is broken in, it will be just what I was after. My point is, one guy may think the 14 isnt loud enough while another guy may think that the 18 is too loud. You really need to just go with what you want. Thats what I finally did.

 

After hearing the 14" I really dont think you would notice any difference with the 18. the 14 is very mellow and almost impossible for me to hear with the radio at about 1/4 volume. Another way to put the g/f hates loud exhaust but said she would like one like mine on her truck. I personally think it would be a waste of money to buy 18". If anyone knows how to make sound recordings or where I could post videos ill make a recording with my digital camera.

 

DAThomas9
Sorry about this late post. I had to change my muffler, order price went up slightly 79.95. Part # is 14263. That is a 5x8x18" in stainless. Buddy of mine worked in muffler shop said go stainless, aluminum will rot out up here in northeast. Still have to wait to find out how it sounds still waiting for delivery 7 days so far.Hope this helps.

 

DAThomas9 Sorry about this late post. I had to change my muffler, order price went up slightly 79.95. Part # is 14263. That is a 5x8x18" in stainless. Buddy of mine worked in muffler shop said go stainless, aluminum will rot out up here in northeast. Still have to wait to find out how it sounds still waiting for delivery 7 days so far.Hope this helps.

 

I have a 5.4 and I want a low rumble, with a decent amount of noise when i get on it. should i go with a 24" or 18"

 

Here is what I can get from all the comments I just read. Apparently, everyone has gotten different mufflers and everyone is happy with the end result. From what I can tell, if any one of us decides to go get an upgraded muffler, we are all probably going to come back to this sight and say, "I got a __________ muffler and it is the best." I think just about any muffler will make any of us happy and the different sizes are simply not very important. Beside, anything is better than the stock muffler......

As far as the size of the stock pipes, I'm not sure. To all of you that are going to be ordering your mufflers off the internet, I suggest calling the manufacturer for assistance because they more than likely have a list of all the stock size pipe sizes for your convenience. There have been a lot of different sizes thrown around and you probably don’t want to make a mistake in your order.

As far as the difference between full cat back systems or just a muffler with the stock pipes, I think that everyone is entitled to their own opinions but the only one that would truly count is someone who has done both. Is there anybody out there that has upgraded to a muffler only, and then went back to change it to a full cat back system???? I think they would have the most experience in this question and would be able to help out a lot.

In conclusion, if someone comes back who has done both and says there is not a huge difference, I will probably go with stock pipes and just do a muffler. As far as which muffler, as stated above, I don’t think it matters as much as we are all making it out to be.

 

Here's a real good FAQ. Take time to read through it. Yes it is trying to sell a product so take that into consideration and do more research: http://www.magnaflow.com/07techtips/faq.asp It answers a lot of questions asked here but does take some time to read through.