[TheTempest]

Okay, basics 101 here;

What are resonators for and why do some exhaust systems have them and some do not?

For that matter, why do they seem to be most prevalent on dual exhaust systems?

Missed this in exhaust basics back when.
Resonators??? Thrushes and Cherry Bombs man...we don't need no stinkin' resonators!

Thanks for the clues.

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Mike
'67 Tempest Custom
Post Coupe

[TheTempest]

Okay, basics 101 here;

What are resonators for and why do some exhaust systems have them and some do not?

For that matter, why do they seem to be most prevalent on dual exhaust systems?

Missed this in exhaust basics back when.
Resonators??? Thrushes and Cherry Bombs man...we don't need no stinkin' resonators!

Thanks for the clues.

------------------
Mike
'67 Tempest Custom
Post Coupe

[Cardo]

I'm not positive what the actual purpose is, but i do know for a fact that they make it quieter. I think that that's all they're for.

[LarryF]

Mike, a resonator is just an additional muffler. Usually it is located closer to the middle or front of the exhaust, where the muffler is often located more toward the rear (no hard and fast rules here). It really comes down to terminology. Here in the USA the terms muffler and resonator are used to identify the main "silencer" (muffler) and any secondary silencers (resonators) that are added. Normally a resonator is added if there isn't enough room to make the muffler big enough (bigger = quieter) or to break up a standing wave (like a pipe organ produces) in a long pipe. The internals can be the same or different, depending on what needs to be accomplished.

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Larry

'63 421SD LeMans...
in pieces in my garage
and basement

[Tom Hand]

Mike, Like Larry said, a resonator is a type of specialized muffler, one tuned to take out specific frequencies. Usually these are found at the rear of the system on new cars but not always. When they are removed, the exhaust might sound louder internally and externally and you might now have certain drones or "resonations" that bother you. Most newer OEM mufflers have resonators of some type contained within them and many of the aftermarket OEM mufflers have been improved to the point that you may not need a separate resonator anymore. Most aftermarket pipe replacement companies sell resonator replacement pipes but they will warn you that the system might be louder than it was with OEM pipes and mufflers. Tom Hand

[TheTempest]

Thank you Tom and everyone else who've responded to this question. I thought they might have something to do with tuning out certain exhuast harmonics. I noticed, at least for the A-body Pontiacs, they did not come installed on every dual exhaust model. The 326 dual exhaust did not come with them and they did not come on certain engine/ tranny combos. I thought that maybe some cars were equipped with lower restricition mufflers and the resonator was added to help tone down what would otherwise be too loud an exhuast note.



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Mike
'67 Tempest Custom
Post Coupe

[Tom Hand]

Mike, one other thing is that you will notice a lot of the V8 RWD cars have resonators towards the rear while the FWDs may have them in the center. So as Larry said, no hard and fast rules on placement may apply. It all depends upon how the original engineers designed the system. Our 65 Safari wagon had them in the rear, right before the pipes turned out the side. The Impala SS also uses this configuration (I believe) but the supercharged V6 later Grand Prixs use a big resonator under the driver's floorpan.
Tom Hand