Hello everyone!

My name is Eric and I just joined the forum. Former Marine and current student who just bought a 2013 5.0 F-150 about 2 months ago. For the last month I have been researching exhaust, primarily Magnapacks. I have read most threads regarding Magnapacks,The Exhaust Guide, and other outside sources. Here are my questions.

1. It seems everyone uses the 14 inch Magnapacks. Is there a reason no one runs the 18 inch setup?

2. If on a scale of 1 to 10 how would your rate the loudness of the 14 inch. The stock exhaust would be about a 3 and your personal opinion of obnoxious loud would be a 10. I am looking for an idle you can hear but not neighbors picketing outside of my house

3. My plan is to do a SI/DO setup. Would running a single Magnapack before a y pipe be best? Also should I invest in an aftermarket y pipe or can a muffler shop do all the piping for me while maintaining quality work?

4. Is it necessary to buy a hi flow cat? The exhaust guide said they are best for tone and performance but multiple threads suggested it is not needed.

Any advice or direction would be much appreciated. Wife finally gave up on convincing me not to get exhaust. Hopefully with have it on within a month

 

14" is the loudest which most people want.

6.5 - 7 for the 14" Magnapack with a tip. At least this is how I feel about my '07 5.4 with stock manifolds and stock cats. It has quite a rumble.

Yes, that is how I ran dual tails on mine.


2009+ it isn't worth adding hi-flow cats as your OEM cats are of the size of aftermarket hi-flow cats in size, and a very little resonator effect.

 

Thank you very much for your reply. I was originally thinking the 14 inch would be a 9 on the loudness scale. I plan on running my setup the exact same with possibly dual 18 inch tips since those seem to be the way to go on this site.

 

On the much louder 5.0 because of the natural engine characteristics, bigger manifolds, and full 2.75" exhaust to 3" after resonator, It may very well be a 7.5 in your case. It won't be awful though. I highly enjoy mine and want more volume to be honest.

Here is a vid of one of your fellow smart allec members on here , he is running the system you want to run. 14" Magnapack with Y piped tails.

 

Funny you posted that top video. That was the sole reason I picked the magnapacks. I guess I need to research sizes more. I thought I needed a 2.5 inch in/out on the muffler and 2.5 to 3 inch on the y pipe.

 

That was the 1997 - 2008s. 2009/2010 was full 2.75", and 2011+ fluctuate a few different sizes between the downpipes/cats, resonator, and after muffler. Run a 3" midpipe and 3" muffler and your all good. Y pipe for dual 2.5" tails.

 

Once again thank you for your help. Just ordered the 14 inch Magnapack, 3 single/2.5 dual y pipe, and 2-3.5 diameter/18 inch/ 2.5 inlet Magnaflow slash tips from Performance Peddler. I will update after they are installed.