Muffler Resonater Question

James Fischer

PCS Member
If anyone could chime in on the question " Do I need to keep the resonater on the exhaust system ??
I have spoken to 3 differant shops to get a exhaust quote...2 of the shops who have been in business for 25+ years say "that you can keep the resonater off and it will actually open it up and get better milage and HP.'
The newer shop says that it should go back on ..but does not need to be there......so what are PCS members thoughts ??
Thank you !!
 
Depends on how quiet you want the car. I left them off on my Chrysler, and it is not as quiet as it originally was with them. Some people like the roar of the exhaust, and others want the car to be as quiet as possible. As for additional horse power, or improved mileage, the resonators will harm neither, if the exhaust is larger than what was original equipment. Loud mufflers make the car sound as if it is going faster, and some people like that sound. Others don't, so the choice is yours.
While we are on the subject, I wouldn't go for the extra expense of a stainless steel system, unless you plan on owning the car for the next 20 years. In my case, I don't, so I used over sized pipes in steel, with a good muffler. One of these days, I am going to get back to the muffler shop, and have them install the resonators. I like quiet.
 
Exhaust System 101, Air Intake Silencer

Resonators are for the control of exhaust noise just like the muffler is in the exhaust system. My 2005 Ford Freestar has one. I would suggest a couple of options.
Option 1] If your car is going to sit for long periods of time between start ups or is going to be run on short runs only where the exhaust system won't be getting up to and staying at operating temperatures for at least 30 minutes, or if you already like the way the exhaust system sounded, DO NOT install one. It will just be a collection point for moisture that the engine generates and will eventually rust out. As the engine is run, water vapor is produced as a by-product of the combustion process. This moisture collects in the cooler parts of the exhaust system, namely the muffler and resonator. Since the muffler is closer to the engine it will heat up faster than the resonator. That leaves the resonator as the last place for water to collect and since the resonator is at the rear of the car and pro-cars are longer than normal passenger cars, the temperature of the resonator and end of the exhaust system will be the last to heat up and expel moisture, thus resonator rust/rot out.
Option 2] If you like an extra quiet-sounding exhaust system, or you want your car to be original as equipped from the factory [if you know for sure that it came with one installed], or you drive your car for long distances every time you start it [and just don't let it idle after you start it and then shut it down after so many minutes every time] and the exhaust system gets to operating temperature and stays there, INSTALL ONE. This is all based on preferences, your preferences on how you want your car to sound when running. Do what you decide to do. This information/suggestions are FYI only, not recommendations. Also if you fall into the Option 1 group, you might want to consider a stainless steel exhaust system, it is expensive but will last a lot longer than regular steel exhaust piping or as Paul posted earlier, if your not going to keep your car forever, then go with regular steel exhaust system.

Not sure what's in front of your air cleaner but by 1974 [73 for Cadillac], GM was putting a duct that connected the air cleaner intake to the inner fender in a attempt to silence throttle/carburetor noise [especially at WOT] and draw cooler intake air from outside the car than from under the hood as had been done for many years. I think GM called them a silencer and they had used them in the 80's on their diesel-powered trucks and cars. I'm not aware that GM had put them on cars in the 70's but you just never know...

Hope this helps.....

Don :specool:
 
As usual, these forums are a great asset to those of us that use them. Although my '72 had one originally, the resonator was left off when the muffler was replaced by a previous owner. I'm having a muffler installed on it today and wanted an opinion from experienced experts.

I also looked elsewhere online:

http://knowhow.napaonline.com/exhaust-resonator-explained/

Put a resonator on it or not? I called Ed and Paul and received opposite opinions. After reading this and another thread, I've decided to hold off and see how quiet the car is without one. I can always add it later...
 
I always put a resonator back on. I, personally, want my cars to be as close to stock as possible. I also want it to sound like it did when it was new. I had to replace everything, from the converter-back, on the '88 Eureka that I recently owned. My exhaust shop did a beautiful job and they put a resonator back on it, as I told them to. That coach sounded like a new car!

In my opinion, it should be a deduct in points, when showing a car, if the resonator is not on the car.
 
My 1962 has 2 1/2" pipes and glass pack mufflers, no resonators. It isn't obnoxious, but it grates on you when you are driving it. I am going to be replacing both glass packs with mufflers, and putting the resonators back on.
On my 1969, the exhaust was done by a previous owner, and they didn't reinstall the resonator. I had the shop install the resonator, and it doesn't make it any quieter. As I said on the phone, you can always add them later, if the car isn't as quiet as you would like.
 
My 1962 has 2 1/2" pipes and glass pack mufflers, no resonators. It isn't obnoxious, but it grates on you when you are driving it. I am going to be replacing both glass packs with mufflers, and putting the resonators back on.
On my 1969, the exhaust was done by a previous owner, and they didn't reinstall the resonator. I had the shop install the resonator, and it doesn't make it any quieter. As I said on the phone, you can always add them later, if the car isn't as quiet as you would like.

What did the previous owner install for a muffler on your '69? If the resonator didn't make any difference, you must have issues ahead of the resonator.
 
That 69 was vary quite when i drove it. None of the 3, 72 i have owned have had the resonators on them all are guite cars. My thoughts on them are just one more thing to rust out. There were a number of small things different between the 88 and 98 in these years. None of which make any difference after CB cut them up and made something else out of it. Pick a good muffler not on of the threw ones and the larger pipe so it doesn't have to squeeze the gasses out. If you only drive the car short runs most of the time the resonator will rust out once a year. You just get tired of replacing it.
 
we moved the 72 combo to clear out the drive way and decided to put some miles on it while it was out from under the cover. made the mistake if checking the oil change sticker. according to the millage it not due yet. but we really need to drive this one a little more. this is why there is not resonator on it.
 
Some random observations:

Resonators help to remove the deceleration rumble at least from my experience with manual transmission cars more than automatic transmissions.

The longer the tailpipe. the less boom or rumble when you let off the accelerator. Quite a difference when you run a car with or without a tailpipe in noise level.

Full size early 60's Ford and Mercury cars at least 352/390 CID had forward mounted resonators under the front seating area. They were short and square, the true muffler was mounted aft of the rear wheels outboard of the rear frame and inboard of the rear quarter panel. I ran a'64 Mercury convertible during my teen years through the resonators only, well until I got stopped for defective mufflers.

Also, when blocked heat riser intake gaskets are used in a car the exhaust note will also change. More harsh/raspy IMO. Not unpleasant, just different.
 
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