Would putting a Gibson or a Magnaflow make a noticeable difference on performance on a 4.6L. If so which one would you guys recommend?

Thanks

 

I had a 2001 crew 4.6L. I installed a Gibson single side swept cat-back. Not exactly sure how much HP it gained but it was definately noticable and loved the way it sounded.....

Gibson would be my pick

good luck

 

I went with the Flowmaster 3" pipes cat back. I noticed an increase in gas mileage, power and sound.

First stoplight out of the shop I hit the gas and just about fell out of the back of my truck. I love it.

 

Had the Gibson super truck, loved the sound, loved the compliments, hated that it only lasted a year. Flowmasters on now, great sound, hopefully last longer, and oh yeah, its cheaper than the Gibson.!

 

I went with a Magnaflow SI/SO, I got the quieter version, but the increase in throttle response, and an extra MPG, was definitely noticable.

 

I have the Magnaflow on my 4.6L & I love it! If your worried about it lasting, get the stainless version, I did.

 

Assuming that you will be installing a higher-flow muffler with Mandrel bent tubing, since the 4.6L is a significantly smaller block than the 5.4, you cannot really conclude that what is good for the latter is good for the former. For stock engines, like most of us have, if you want to definitely maintain your SOTP low end, go with 2.25" tail pipes. If you are willing to sacrifice your SOTP low end power, but gain on the upper end, go no bigger than 2.5" tail pipes.

I learned this the hard way. I noticed a significant SOTP low end loss with a Gibson SIDO catback system on my 4.6L. I am not the only one on this board with this complaint.

Good luck

 

I did a lot of reading on exhaust setups, and I configured my exhaust based on the type of info above, that was repeated on many occasions.

If you tow with a 4.6, definitely take Kali's advice.

I swapped out the muffler only, and left the stock pipe to the rear intact. It worked well, better response, and a bit more power, and it didnt knock out the bottom-end at all.

 

>>>>I installed a Borla single in single out system on my 5.4 SuperCrew. It sounds great and was what I was looking for. It's not for those who want a very loud system though. It does have an aggressive sound during heavy acceleration but during normal driving it has a nice rumble to it while not giving you that annoying in cab drone to deal with. I did feel a slight increase in power on the truck, but it's not like your gonna feel a tremendous difference in any aftermarket exhaust system. As most of us Screw owners know the truck's rear wheels do not break traction very easily, even with the 5.4. Since installing the Borla I've noticed that if I accellerate from a stop quickly the truck now has more of a tendacy to try to brake traction. My fuel mileage has shown a slight increase as well. The Borla SOSO system comes with a 3 inch stainless steel mandrel bent pipe, 3 inch straight through muffler, and I believe its a 4 to 4.5 inch polished stainless steel tip. The hangers borla attached to the pipes and muffler matched up the the trucks hangers perfectly. The 3 inch pipe is fine for a single pipe system to maximize horsepower/torque and still not lose low end torque. For a duel system it's best to use a 2.5 inch pipe setup to still gain good power while not lose low end torque. Whatever catback system or muffler you go with, if you go with a quality system like Borla or Magnaflow you wont be disappointed. Just don't but expecting to gain huge horsepower and torque gains. But they are great bang for the buck no doubt. I'm extremely pleased with the Borla system,it's design, it's peformance, and it's quality.