I was installing a new catback flowmaster system this weekend on my own. I have a 97 with a 5.4. I cut off the stock system right before the muffler so all that was there was the cats. I ran the truck up and down the street and it was still fairly quiet, just a little bark. The cats act like a muffler on their own so dont expect to be to loud just cutting off the muffler. I had a 2000 with a 5.4 a while back. I had a muffler shop install duals after the y and added a set of small glasspacks. That was the best sounding truck I have heard. It was only $250

 

would cutting off the stock setup like that be a bad idea for any reason? I dont want to do it if it is going to lose me some power, or fuel efficiency or anything like that...

 

I removed my cats and it gave my truck a deep rumble. Not loud. The other day, I unhooked my muffler just for kicks. It was so loud!!! It was insane!!! I didn't know that truck could make so much noise. It was so rediculous, I wouldn't recommend running strait pipes all the way from the engine!

 

So you just removed the cats (all of them? 4 right?) and left the rest of the stock setup? That's really what I want is a deep sound.!!

 

Removing cats = bad idea. Need MIL eliminators and fuel economy will probably drop.

Just spend the $30 to put in that straight pipe. If you don't like how it sounds, then worry about adding some kind of muffler.

As for any question about tips, buy on that looks good to you. It will have very little difference on sound unless it is a megaphone style that increases diameter towards the end of the tip.

 

Yeah that is what I would really like to do, but the exhaust shop told me it would be $80 for a single and $130 for duals, is pipe really that expensive to buy?

 

Pulling out the cats isn't going to make it louder. Most shops will not bypass cats, it's illegal except full off-road use only. You will need to rig in the NO sensors after removing the cats. Straight pipes from the cat back will be loud, think racecar loud, not so much at idle, but under load. Without the muffler backpressure, low end torque will drop. Ask any of the flowmaster owners. Any work a shop does, it's more than just the pipe costs (labor, shop use, profit).

 

look, don't run without a muffler, some people will think it sounds good, but anyone that knows anything about exhaust will know that it's a straight pipe just by the crude sound it has. For a "GOOD" sound, put on a muffler. If you want loud, go with either a flowmaster 40 series... if you get the 40 Delta flow, that will decrease interior resinance, or a magnaflow. If you want a quiter truck with a muscle sound, get a gibson muffler. You can install all this yourself... just order the muffler and go to your parts store, get a small section of 2.5" tubing, make sure one end is flared out so it's 2.5" I.D. instead of O.D. and three 2.5" exhaust clamps. Cut off the old muffler, attach the new one, clamp in place.... cut and install the pipe you got from the store, clamp onto the muffler and the tail pipe... you're done. It will sound like a tuned muffler and won't cost too much. I should imagine it will cost you less than $100. Your other option is get a flowmaster catback system, which won't be more than $300, that will give you everything to put a new muffler and tail pipes of your choosing on the truck; won't take but a couple hours and some simple hand tools. Just whatever you do, don't run a bypass pipe... it sounds obnoxious. Also, don't screw with the cats, you're looking for trouble if you do; leave well enough alone. A tid-bit of info, engines need backpressure to be able to create low RPM torque; take away too much restriction and you'll loose your low end torque. The only benifit you get from removing cats and running true duals and things like that are increased flow for MAJOR engine mods.... things such as superchargers, head and cam swaps, stroker engines.... things of that nature. There's a formula for displacement and output for what size pipe(s) you should run and backpressure needed. You'll be all set with either a new muffler or a catback system. Good luck!!

 

Good Stuff Guys, sounds like you really know what you are talking about! I really appreciate yall all chiming in. Backpressure is something I was worried about when removing the muffler and putting straight pipes in and although I dont know much about it I had inferred that removing the muffler would decrease it. Sounds like I should just get a new muffler and I think I will just go with the Gibson and do it myself, or have my pops help me. So the Gibson will give me a deeper growl? That is the sound I am most looking for, I really dont want it to be really obnoxious; I will probly give it a try here pretty soon. So, Nate, the setup you are talking about I would keep the stock tailpipe, right? And there wouldn't be any welding needed? Thanks, Hawg.

What Gibson muffler would you recommend?

 

Just replace the muffler w/ pipe, not the whole tailpipe. The stock tailpipe will flow better than a crush bent hack job anyway. $30. If you don't like how it sounds, then all you wasted to try it was $30.

The only reason to go dual is for the look. Don't do dual unless you get some nice tips. But, all that costs money and won't do anything for how it sounds.

 

I agree with APT. I just had my muffler cut off yesterday and replaced with a piece of pipe for $40. The muffler man had to add a hanger and bend the pipe because the muffler inlet and outlet was offset. I love the sound! It sounds deep and mellow and looks stock. There is plenty of back pressure from the 4 cats that are still on. I highly recommend at least trying this method.

I edited it to add that my engine is a '99 4.6L

 

Alright, I'll do it, I'll try it!! Won't be out much and it cant hurt to try if I dont like it I'll get a muffler.

 

You won't be disappointed!

 

97 f150...flowmaster exhaust...still not loud enough...i understand i have 4 cats and i think this spring i am going to cut 2 of them off for a lot more rumble...how much work is it really going to be if i decide to chop 2 of them off?? and will these missing effect my 02 censors or check engine light...if so what needs to be done to fix that????


Thanks

 

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