I have si/do flowmaster orginal 40, it's just NOT cutting it, I know get rid of cats and muffler and it'll purr, but that's illegal..I asked a guy at the shop if could get a Y pipe in place of the muffler he said it would make it a little louder, any other things i could do, and i like the look of my exhaust tips.. thanks in advance, I tried this in the f150 04-06 thread didn't get much response..

 

Other than removing the cats, it's not going to get much louder. If your's has 4 cat's, you could make a new y-pipe with only 2 high flow converters.

 

Ok, thanks, how do I tell if I have 4 cats or 2 cats?

 

You just have to look, there should be one by each exhaust manifold, then 2 more farther back.

 

I've seen the ones farther back ill have to check for the other ones..

 

Removing any of the cats is gonna be illegal. Feds prohibit their removal unless improperly functioning, then only with an approved replacement. Of course you can get around that by doing work on your own vehicle, but you'd need the CARB or 50 state legal paper work if you have emissions testing in your area regardless of the mod if they do a visual and question it.
You have a factory y pipe before the muffler. There are replacement 'y' pipes out there. By going with an aftermarket 'y' it may improve flow characteristics, as well as change the tone. Remove the muffler or change the style is also another way.

Remember sound is energy, just in a different form. The closer you move the exit of the pipe to the engine the louder it will be, less of a chance of it being dampened out by the insulators and muffler. You can always go with a set up that exits in front of the tires with a bigger resonator. If anything, you'll hear it, even if the exhaust isn't actually louder since you've moved the exit closer to your ear. Not exactly what you wanted, as you want to keep the tips... but those are the breaks.

-Kerry

 

Well, we d ont have emissions test, this is alabama lol, I heard one f150 with a 5.4 and I don't know WHAT he had but well he was EXTREMELY loud like louder than mine i'd say twice, and a kid down the street has a tahoe open header, I know he didn't do the work and you can hear him from a mile away.. so i dono lol