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Hello guys/galls
alright, i have an 03 ford f150 which i just replaced the muffler from stock to get a more manly sound out of my truck, but alas it wasn’t to be. They told me it was because i have 4 resonators on my truck, is this normal? they also said they are wired into different parts of my truck, i if i were to remove them would that be bad? please any help would be greatly appreciated!

Are you sure they said resonators and not catalytic converters? The cats are required for the engine management, and you really want to be careful messing with them. Your truck should have 4 of them. Replacing them with a more generic version may cause endless ‘Check Engine’ lights. However, a lot of performance exhaust companies offer ‘cat-back’ systems that replace all the exhaust from the catalytic converters to the back of the truck that should get you the sound you’re looking for.

Also, if you live in a state with emissions testing, you will automatically fail if your CEL is lit. Then you have to undo all that work you did anyway. If you decide to change the catalytic converters, be sure to get a guarantee that the new system won’t make the ECM throw up.

Normally each exhaust pipe will have an exhaust manifold, cat converter, a muffler, and a resonator. The resonators are there only to control sound. Their removal would have no functional effect. However, in addition to the muffler you also have the exhaust manifold and cat converter that affect sound, as well as an induction system designed to control sound… which has its own resonator.

It ain’t like the old days. These days, if you want to get the “manly” sound, you need to invest some bucks in everything behind the cat converter and perhaps replace the intake too. Replacing the exhaust manifolds with headers would make a big difference too, but in your case I think the cat converter is built into the tail end of the exhaust manifold, so there may not be a set of headers for yours, I don’t know.

Bottom line: you can get the manly sound you seek, but you’re going to have to have a manly wallet.

Stick to ‘cat back’ systems, don’t want to screw up your truck. Borla sells them for your F-150, have you check out Jegs, etc?

Resonators wired into your truck? I’m with the others. I think they meant catalytic converters. I still don’t know what they meant by “wired” unless they looked at the oxygen sensor leads and assumed it was powering the cat or something.

Either way, if what you said they said is really what they said, you should find new people to look at your truck, because they don’t know what they’re talking about.

As others have said, removing the cats would be bad, illegal, immoral, and cause your check engine light to come on.

Removing a resonator wouldn’t hurt anything except your wallet (you’ll have to pay to have a straight pipe welded in where the resonator was), but it might make your truck sound bad. Resonators are there to adjust the tone of the exhaust - sometimes just to quiet it down, but other times to strip out frequencies that wouldn’t sound good if you could hear them. Your truck might start sounding like a heap if you removed resonators.

They’re also the last line of defense when your muffler gets a big hole in it - without the resonators your truck will be as loud as a race car, which is not only very unpleasant when you’re not at a race track, but will get you ticketed if a cop hears it.

An 03 F150 has no resonoator.
It does have four cats and four O2 sensors all of which are prior to the one muffler easily affecting the sound .

Nice catch, Ken. A tip of the hat to you.

Teenage me had a early 60’s Ford Galaxy, and while I was perfectly happy with the way it sounded, my dad thought I needed it to sound better, so he had something called a “glass-pack” muffler installed. It did change the sound from a muffled “whrrrrrrr” to more sharpened yet still muffled “rat tat tat tat” sound. Do they still make that type of “glass-pack” muffler?

they do George, I have them on my truck


…i just replaced the muffler from stock to get a more manly sound out of my truck…

Um, you’ve confused manly with noisy. If you want it to sound manly, put loudspeakers in the bed blaring the voice of James Earl Jones or equivalent. Of course that would end up just being noisy too though.

I remember ‘cherry bomb’ glass packs…

Me too, and with good memories.
They just don’t sound as good with 4-bangers and their 180 degree cranks, however. Ergo, “fart cans”!!

To get good sound out of an exhaust system you have to put good sound in; and that takes 8 or 12 cylinders, IMHO.
This concept is lost on the “ricers”.

Concept also lost on Ferrari on models with their “flat-plane” V-8 crankshafts. It may sound good to Italians at 9,000 rpm, but no idle burble at all. My brother’s V-8 Maserati at least has a good old American style cross-plane crank and a melodious burble at idle.

I wonder what those Formula I Grand Prix cars use. They sound pretty good. Of course the only thing I actually know about them is from watching that movie “Rush” … lol … I think modern Formula I racing cars use a fairly small displacement engine, V6, 1.6 L.

The biggest restriction in your truck’s exhaust system is the catalytic converters. Gutting those will make the truck louder, not more manly, and will cause more problems than you desire.

Texases mentioned a Borla exhaust and I would second that. I put a Borla exhaust on my oldest son’s '96 Camaro and it sounds fantastic.
It provides a subdued growl without being headache or cop bait noisy. From memory, the Borla is also stainless steel and has a lifetime warranty.

Yes, F1 uses a 1.6L V6, but it is turbocharged, runs up to 16,000 RPM, and has around 600 HP. Also, there are 8’forward gears and the car has to weigh at least 1520 #.

1963 Ford Galaxies had mufflers at the very back of the exhaust system they tended to rust out in no time as the water vapor settled in them with very little heat. I replaced them with 30 inch glass-packs on my 427 cu in. They sounded good and not all that loud. I ran them in Oregon for over a year with no problems. When I took the car to Southern California I was very politely informed by LAPD that it was just a bit loud. I added turbo mufflers ahead of the rear axel. It was a bit more subdued and actually sounded better.

It’s pretty amazing @jtsanders that those F1 cars get 600 HP out of the same displacement engine as my 1990’s econobox. Which gets maybe 120 HP. The Wikipedia article on F1 cars is pretty interesting. Like you say, the turbo charger is part of the explanation. It must really blast air through the system and must get really hot. Good thing the engine – according to the article – only has to last a few thousand miles between rebuilds. It also says there’s a good deal of energy recovery going one in those F1 engines. The temp difference between the exhaust manifold and the intake manifold is used to create electricity, which powers electric motors, boosting the HP even more.