I found the responses in this thread very funny. Has some bad words in it, but thought some here might take a trip down memory lane and find it funny, too.

"Any idea how much et I’ll gain flipping the air cleaner lid over? Asking for a friend. 3/4 cam, headers and a Rochester 2 jet carb. Fresh set of points if that matters."

https://phantombullet.net/threads/flipping-the-air-cleaner-lid-over.22122
 

Well...This isn't "flipping the lid" but on a 70-1 340 using the taller 440 air filter raises the lid a half inch and that is worth a solid tenth in ET

I know that I reached the limit of the 68 un-silenced 340 air cleaner. The AR ratio’s would go rich at high rpm. Modified the base and the issue went away.

Depended on the type of air cleaner, if one little snorkel tube turning it over would slow air to come in better. The unsilenced ones didn’t since it was open already (couldn’t do it anyway it’d be holding the hood up) but the sound made it fly!

Watch Engine Masters Air Filter Shootout

They even test the Mopar Dual Snorkel

https://www.facebook.com/watch/?v=153247265330893

Definitely a cool shot-out. It would have been perfect if they had ran the Mopar big oval, too.

I always thought that flipping the lid was a Chevy thing. I don`t remember being able to do it on any Mopars that I owned.

it's the sound of POWER !

Me too! Those ole Qjets would howl at WOT!! My buddy ran a highly modded Qjet on a strong 400 in his GTO. The car was fast and you could hear him for miles if he was leaning on it....loved that sound! He still has the car to this day!

Many mopars in the 60s and up had tops that could be flipped. I flipped the one on a 62 Plym 318 poly, mom could hear it two blocks away. Wanted to know what I did to her car? I put it back real quick

I flipped the lid on the air cleaner because it was attached to the rest of the car. Good thing it was not a convertible.

Guilty as charged...so long ago I don't recall which cars I did that to.

Poverty Ram-Air !

Seems the best answer is 1-2 db(A) Also can you actually flip a Mopar "unsilenced" single 4bbl air cleaner lid, (I know were talking a Chebie or something else, not a Mopar.......Just asking for a friend )

I'm not ashamed to admit that was one of the 1st things I did whenever I bought a new to me Mopar (after a tune up and oil change). Loved to hear those 4bbls sucking air through them. Didn't much care if it made much HP or not, it was all about the sound.

Exactly!

Some things are subtle.
Does a loud vehicle get better fuel economy because the driver slows down without really realizing?

Have you ever driven a really quiet rental car on a mostly empty highway, then looked down at the speedo and thought “Whoa, that’s way faster than I thought”.

We hopped up my 95 Cummins adding pump cam plate, pump timing, exhaust and governor springs many years ago. Ramped the boost up to just over 35psi. The filter minder in the housing said the air filter was plugged. Installed a new filter, ame result. Removed the filter element, same result. Cut the front of the filter box open to increase the square inches of filter inlet area. Never had the issue again.
Doug

Back in 80 My brother and I bought our 73 Charger Rallye 400 Magnum. The guy before us has flipped the Air Cleaner lid. We went to flip it back and the Sticker that said 400 on the lid was permanently charred from one of many previous Thermoquad fires. LOL
Needless to say we kept it flipped until we got a new air cleaner.

Can't say if it helped with power or made it louder but it looked better than the cooked top side of the lid.

i pulled the cone shaped silencer out of the air box/inlet tube thingy on my caravan.
didn't have the same effect as flipping the air cleaner lid on the oldies.

Dang that's funny!!!