Stock Air Intake Resonator....What's It Really There For?

[Laga]

And probably gained nothing at all except some noise.

It didn’t even change the noise. It was referred to as a hydrocarbon trap more than anything else.

 

[Juice]

I mean, I could name a few mods I’ve done in past that we’re purely for noise. That’s half the fun!

We have a Harley owner here?

Lets get back on track, we were discussing intake resonators/chambers. hehehe

 

[GlassTop09]

Below is a study done using a Ford 3.0L V6 engine to see if using 1 of those intake resonators was effective on engine TQ output for those interested:
pg 26 is the conclusion if not wanting to read thru the entire study............

Essentially these intake resonators application only showed to be effective below 1,000 RPM's & the effectiveness is very small--<2% comparing engine output w\ resonator installed vs w\o. Above 1,000 RPM's there was virtually no difference since the frequency generated by the engine's air charge was in excess of the resonator's capacity to affect.
Thus the main effectiveness of these resonators from a general perspective IMHO is primarily noise cancellation w\ the TQ improvement from better air charge cylinder filling during intake stroke being more of a red herring from a practical view.

Enough data to verify it does work but not enough TQ output difference to notice.......

Interesting study though....................

 

[Juice]

Yea, I figured it was a small difference if even measurable. But as the required fuel economy increases, OEMs start looking at even the smallest improvements if cost effective to implement.

 

[Rich]

Below is a study done using a Ford 3.0L V6 engine to see if using 1 of those intake resonators was effective on engine TQ output for those interested:
pg 26 is the conclusion if not wanting to read thru the entire study............

Essentially these intake resonators application only showed to be effective below 1,000 RPM's & the effectiveness is very small--<2% comparing engine output w\ resonator installed vs w\o. Above 1,000 RPM's there was virtually no difference since the frequency generated by the engine's air charge was in excess of the resonator's capacity to affect.
Thus the main effectiveness of these resonators from a general perspective IMHO is primarily noise cancellation w\ the TQ improvement from better air charge cylinder filling during intake stroke being more of a red herring from a practical view.

Enough data to verify it does work but not enough TQ output difference to notice.......

Interesting study though....................

I tried reading the entire report, but after a few pages I got lost in the technical jargon. It seems there were only minor effects at 1k rpm so that we're talking a small reduction of noise at or around idle speeds. Most cars don't idle at 1k rpm anyway so it's kinda moot. Thanks for sharing that document!

 

[GlassTop09]

Yea, I figured it was a small difference if even measurable. But as the required fuel economy increases, OEMs start looking at even the smallest improvements if cost effective to implement.

Yep.....also it's good marketing ploy as well to drive\boost sales among the masses.
By this account Ford should've sold more 08-09 Bullitt's as the production Bullitt's 85mm CAI has 2 of these resonators installed in it's air tube....things are large enough that they take up all the space under the tube in front of engine....maybe these resonators along w\ the open filter, airbox design of the CAI are the reason why a Bullitt's 4.6L is rated for 315 HP instead of 300 HP (avatar pic).....

I do know this, this Bullitt 85mm CAI can flow a LOT of air as to date we haven't exceeded it's capacity on the dyno yet....even w\ a dust sock installed over the filter (picked up peak HP\TQ over prior run peak HP\TQ numbers w\o dust sock installed w\ no loss under the curve at the low end)....wonder just how much of this flow capability is contributed to the resonators vs the open filter\airbox shield\MAF housing design? Very quiet in operation though.......

Food for thought..................