Air cleaner snorkle question

[Robert M.]

Hello,
I've not asked a question in a while, so here goes. Earlier Dennis posted some photos of a late 70 l-46 air cleaner, the enclosed variety.
What is the purpose of enclosing the air cleaner? and the dual snorkels?

I assume sound reduction.

[Jeff W.]

Re: Air cleaner snorkle question

Good question Robert as I have thought of that many times. For driving around I use an air cleaner lid from an open air cleaner set up that leaves about a 1 inch gap around the outside of the air cleaner. I do enjoy hearing the secondary's kick open where as fully closed you hear very little. I hope someone reply's with the thought behind the design.
Jeff

[Larry E.]

Re: Air cleaner snorkle question

Hello:

One classic example of this would be the 70 Z28 with the LT1. It had duel snorkles. You would
think they would have put the open element A/C on it like the Corvette.
They put it on the L34 and not the L78! One possible reason was that the
air intake was an underhood design rather then a outside hood intake like
the 1969 H/P Camaro. I believe John DeLoren had something to do with
this. I hope others would chime in on this.

Larry

[Stuart F.]

Re: Air cleaner snorkle question

Don't you suppose it may have had something to do with the emmissions controls. I forget what they called that, something like "thermac", where they used preheated air from around a stove over one of the exhaust manifolds piped to the snorkle for use during the warmup cycle and controlled by a thermostatic vacuum switch and valve. The performance cars were not immune to having these devices. I had a 83 Camaro Z-28 H.O. that had a twin snorkle air cleaner with the two thermac valves, and a chrome lid. I too changed to a tall element which jacked up the lid about an inch. The lid would just barely rub on the underside of the hood (Darn!).

[Joe L.]

Re: Air cleaner snorkle question

Don't you suppose it may have had something to do with the emmissions controls. I forget what they called that, something like "thermac", where they used preheated air from around a stove over one of the exhaust manifolds piped to the snorkle for use during the warmup cycle and controlled by a thermostatic vacuum switch and valve. The performance cars were not immune to having these devices. I had a 83 Camaro Z-28 H.O. that had a twin snorkle air cleaner with the two thermac valves, and a chrome lid. I too changed to a tall element which jacked up the lid about an inch. The lid would just barely rub on the underside of the hood (Darn!).

Stu and Robert------


Thermostatic air cleaners did not begin on Corvettes until the 1976 model year. Notwithstanding that, I believe the change to the closed element air cleaners during the 1970 model year was somehow related to emissions control. Just how they provided for any improvement in emissions control, I do not know.

[Jack H.]

Re: Air cleaner snorkle question

All that comes to my mind is the length & diameter of the snorkles could be 'tuned' to a ressonant frequency to fine tune air flow...

[Alan S.]

Re: Air cleaner snorkle question

I also always thought there was a technical reason for the change since the dual inlet base would seem to cost more to manufacture than the open base. Too many dollars to make the change just for 'style'.
Regards,
Alan

[Stuart F.]

Re: Air cleaner snorkle question

I think it is like the racing sports cars of late which use an inlet restrictor to sort of govern them down to the competition. Yea! That's it! it was to give the Mustang and other muscle cars of the era a chance to compete for performance. Ah the General! there are some real sporting guys.

Stu Fox

[Chuck S.]

Re: Air cleaner snorkle question

All that comes to my mind is the length & diameter of the snorkles could be 'tuned' to a ressonant frequency to fine tune air flow...

Or, to suppress that giant sucking sound when the secondaries opened. GM might have thought that Corvettes were pretty expensive cars for most customers to favor that "no air cleaner" sound.

Snorkles were around long before efforts to control emissions were a concern. Early snorkles were tapered with the inlet end smaller than the outlet, like a diffuser, or to contain intake noise.

[Jeff W.]

Re: Air cleaner snorkle question

Not sure who let those people into the design center because that is my favorite sound!

[Lawrence M.]

Re: Air cleaner snorkle question

I think the enclosed air cleaner was an early attempt to reduce engine noise in the face of impending Federal noise reduction laws.

Larry

[Stuart F.]

Re: Air cleaner snorkle question

If we're going to point the finger at sound, having lived through the period, I'd have to say it was an early attempt to make the Corvette reflect some level of civility. After all, they were only found on the lower performance engines and the folks that ordered those tended toward more civil automobiles like say the T-Birds of the era, i.e. they wanted their cake and to eat it too. And the "Ladies" even ordered Powerglides (or they were ordered for them by their Sugar Daddy).

Stu Fox

[Chuck S.]

Re: Air cleaner snorkle question

Not sure who let those people into the design center because that is my favorite sound!

For me, intake noise at full throttle is reminiscent of my old high school "speed mod" of removing the air cleaner.

To me, it is a raw, cheap sound that symbolizes a lot of "heat and light", and not much else except backfires and exceptionally poor gas mileage. And that doesn't consider that removing the air cleaner was completely devoid of responsible maintenance practices, but then we were kids.

Of course, the effect resulting from this sucking sound is completely dependent on the engine making the sucking sound; in my case it was a 139 cubic inch, flat head truck engine. I think the time to cover the quarter mile was like 30 seconds, but we were measuring it by counting OneMissisippi, TwoMissisippi...; an hourglass would have been more accurate.

My transportation preference would be a vehicle like these UFOs some people describe...effortless, instanteous translation from point A to point B with zero sound. My first late model Corvette was a start in the right direction.

You know what Teddy said..."Walk softly and carry a big stick." Or, to paraphrase Forest Gump..."(Horsepower) IS as (Horsepower) DOES".

[Stuart F.]

Re: Air cleaner snorkle question

Chuck;

You crack me up! You know, I still have a beautiful chrome bonnet air cleaner (hog hair or wire mesh?) that I first used on my Dad's 40 Chevy, and that was before I had my license! The thing had a milled head and ran pretty good. My Dad never knew I put that Air Cleaner on there until one day he complained about the noise it made (he had a hearing aid) and I had to fess up. I never thought he'd notice as I always changed his oil. I convinced him to leave it on based on improved gas mileage!

Stu Fox