November 30, 2007Hey, I have a 2004 heritage f-150(old style) with a 4.6l and I had true duals with flowmaster supper 44's and an x pipe installed. It sounds good but i would like it to be louder, if I replace the 4 stock cats with 2 high flow magnaflows will that make it alot louder, also do i need the cats to have any o2 sensor holes when I order them?
November 30, 2007yes, it will make it louder. I think the exhaust shop has to weld new bungs for the O2 sensors but im not sure.
December 1, 2007in my opnion it does make a diffrence alittle not worth all th money youll spend.. if i could go back in time i would not waste the money
December 2, 2007The difference is simply night and day, worth every penny IMO.
December 2, 2007. It is an amazing difference. And well worth the money.
December 2, 2007when going from 4 cats to 2 it will be louder. not by much, but louder
try thunderbolt cats off ebay. they are owned by magnaflow and a lil cheaper.
50 bucks brand new off ebay.
December 3, 2007I have 2 thunderbolts in place of the stock 4 cats, best thing i've done, these things are about 6"s of converter!!!
December 5, 2007Defintiely will make a difference!
This was on my '02 4.6 SuperCrew.
December 30, 2007I have a 1998 Ford F-150 with the 4.6 and I took off my cats at work and welded in a peice of pipe in its place and put a Flowmaster 10 series on it with duals out the back. No muffler shop would take the cats off, so I had to do it. It was a pain in the butt but it made a huge difference in sound. My check engine light hasent came on yet and I did it in summer. It deffinatley catches peoples attention and it sounds good.
December 31, 2007One of the best mods I did was replacing the cats with 2 high flow cats.
It is about 3 times louder..like night and day,,worth every penny. Go for it!!!