I am going to order a magnaflow for my 05 4.6L, I heard recently someone saying that the 18" was not loud enough. Should I get the 14? I want a deep low tone at idle. I am dumping at the axle si/so... Also, should I replace all these cats with magnaflow hi flow cats? Would that benefit the performance enough to make it worth the money? Thanks!

Jon

Also... I noticed the round mufflers are cheaper than the oval... Any reason not to go with round?

 

Anther question. Do I get 2.5" SI/SO or 2.25" SI/SO?? Im pretty sure the pipes on my truck are 2.5, but would I be easier to slide the muffler in to weld? Thanks

Jon