Another muffler question

[jaslo]

Hey guys

 

I have done this before where I replaced the factory muffler with a magnaflow. I did that on the 2001 with 4.8 V-8. I already had a k&N fipk on and then replaced the stock muffler with a magnaflow and left all the factory pipes, but just put a chrome tip on the end. Now I have a 2004 5.3 V-8, I plan to do no engine modifications but just want to replace the stock muffler with a magnaflow. Has anyone does this recently and have you noticed any increase in HP and MPG? When I did this with the 01 I didnt really notice much difference but I did like the sound of it.

[Roostman]

Just do it and call it a day. Your not gonna feel 10-15 HP in the seat of your pants on a rig that already has close to 300 HP. Now if you get 10-15 HP gain out of a motor that had 150 HP, youd more than likely feel a difference. You can expect to gain a MPG if you drive the same as you did with the stock muffler, but nobody does cause it sounds so much better with a performance exaust. My $.02