Does anyone know if removing resonators on the 5.0s decrease torque? I read somewhere a while back that part of the reason they are there is to maintain back pressure, which if reduced by removing the resonators can lower TQ numbers.

I'm not sure how accurate this is, and hoping someone here can shine more light on this topic.

 

So yours are dent toooo!! Thought it was just me

 

Thank you for the info....I will look into replacing mine or having them removed totally. I am more for letting the engine breathe naturally....I have been hashing over installing tuned headers with new pipes to the borlas.....

 

Monster, I have done a little research on removing resonators and learned two things
First, it may cause drone in the cabin, this is dependent on your mufflers because some allow more drone than others.
second, it does reduce back pressure in the exhaust system, which is the purpose of the resonator. A resonator does two things, muffles sound and maintains back pressure for efficient operation of the engine. Removing resonators may cause a decrease in gas mileage.
Ford designed the system for the best efficiency of the engine, removing the resonator is contrary to the original design.
I would suspect that torque will be reduced as well, hopefully someone on the forum has done dyno numbers on before and after resonators removal that might confirm the torque numbers.

You have to ask yourself, why did Ford put the resonators in the system? We all know they won't spend money for items /parts that are not essential for the vehicle. If it was for sound reduction alone they could have used a tamer muffler, but they didn't, so they must have done this for back pressure and efficiency.
Just my two cents

 

Just when I was convinced I was going to delete mine....

I didn't buy my car for MPGs, but I'm not interested in potentially losing power AND mileage.

 

^ This. This is exactly what I was thinking. Thanks for sharing. It would be great is someone here has dyno data to support or disprove the theory.

 

Interesting, I think I might have lost a mile or two per gallon around the time I removed my resonators. I thought maybe it was driving habits. Now I am not so sure.

 

That would be a hard one to determine. When the car sounds better, you're more inclined to drive harder.


I think my car would get better mileage with its Steeda intake and tune than stock, but I have too much fun listening to it. Plus, the GT 500 quad tips sound great. I find myself switching to manual shift just to hear it burble when downshifting.

 

I'm pretty sure that the purpose of the resonator is for sound reduction ONLY. Not HP, not TQ, not MPG (engineers and smart guys/gals chime in here). Look at the 2015 GT, it has a giant resonator (single) way up early in the exhaust...it's a big reason the 2015 GT is quieter than 2011-2014. If you have no drone before removing the resonator, most likely you will have no drone after removal. Removing the resonators will not ADD drone. If you already have drone from an aftermarket muffler, then you will probably still have drone after removing the resonators. I have a 2011GT, with GT500 mufflers, resonator delete, absolutely NO DRONE whatsoever.

 

I actually am an engineer in the auto industry, but this is a little outside my wheel house. I have a somewhat educated guess that there is more to the resonator than just sound. They have been historically used to create optimal back pressure. But I'm not sure if that is why they are on the Coyote.

 

I always assumed (and that can get me in trouble) that the resonator is designed to tune out some frequencies and possibly enhance others. The muffler reduces sound across the board.

 

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More than just a pretty face, huh? Smarty pants!

 

I am not an engineer, but I believe the back-pressure theory is correct. Just as an FYI, There should be a dent in each resonator. It's designed that way. Now if there is more than one rectangular dent, then yeah, it's from rocks and other debris, but the resonators are not perfectly round.

This isn't the 90's anymore when we had stock V8's coming with 225-250 HP. These new engines are designed to eek out maximum HP and Torque as is. We have to be very careful of the mods we use.

The days are long gone when you could add a CAI and gain 10-15HP. Or pop in a K&N air filter and expect a 5HP gain.

These days the best way to add power is to supercharge or rip open the motor and start replacing stock internals with stronger parts or both. A tune might be good for 5-10HP. But if you want more than that. It's going to cost $$$$.

As the Sign said in the original Mad Max film at the mechanic's shop. Speed is only a question of money, how deep are your pockets?

The Corvette Stingray comes with a 6.2L engine producing 450HP. We run a 5.0L engine, that is a huge difference in size for not much gain in HP. The 'vette makes up the difference in weight, tuning, and tires. The GT350 will have a 5.2L engine (Flat Plane Crank) and produce probably around 500hp.

Weight, displacement, and Forced Induction are the best ways to get the most out of your engines nowadays. The car manufacturers are taking every opportunity to make as much HP while staying within a certain dollar amount figure.

Also, Displacement is quickly being left behind in favor of Forced Induction. Twin Turbos, and/or electric motors. the Porsche 918 Spyder has a 4.6 liter engine producing 608 HP (built with internals to withstand those kinds of numbers) and gains another 280 or so HP from the electric motors it employs. My favorite part of the 918 though? Watching it spit a constant torch-like blue flame out of each exhaust under acceleration.

Ford's response to the Challenger Hellcat was that they were "going in a different direction" tells me that they are looking to the German car manufacturers for inspiration. Reduce Weight, add turbos,make it as efficient as possible, and make it corner like it is on rails.

Chevy's new mid-engined C8 that's coming is also looking towards the future. Chrysler is behind the times.

 

Doug...going a little off-topic, are we? The OP is trying to determine, what, if any, negative affects he will have if he removes his resonators.

 

Your cats create more back pressure than the resonators. That's why you gain more hp by removing the cats. Also, my mileage didn't change when I went with an OR h pipe so your mileage shouldn't change with deleting resonators.

 

LOL, that's what I keep telling my wife

I can tell you A LOT about vehicle dynamics, electronic stability control, microprocessors, control theory and model based monitoring. But I only have a basic understanding of what part the resonators play, and engine tuning. The Force is weak with me here

But I like this thread! I like learning new stuff

 

That's true, cats are restrictive. But I don't think they are the primary tool in tuning back pressure. Cat materials are precious, and you don't want to use larger cats than what you need to meet emissions. I think that's why you have resonators further down the stream.

But on the flip side, pretty much all Cat-back systems remove the resonators anyway. And I'm pretty sure that if you have any TQ losses due to loss of back pressure they are made up by increased flow and/or tuning.

 

My friend I think if you stay a few nights at a Holiday Inn Express your knowledge of resonators will be greatly expanded and then you could teach us all about them!

 

I have the same issue, and I solve it the same way :-)

 

And I think you win the interwebs today . That was strategically placed