With a cowl hood setup (no flapper), would the cowl hood flow enough air at lower speeds to give enough of a benefit worth mounting the air filter as high as you can go into the cowl section of the hood?

I don't have the air cleaner with the sealing base...just an open element filter.

I think I've seen air cleaner spacers that will let you raise the air cleaner up a bit.

On my last car, feeding the engine cold air made a big difference in low end throttle response...but that was a supercharged car. In an NA motor, does it help as much?

The engine bay is really hot when I pop the hood after a drive...colder air must be better, right?

Anyone done this?

If you have a front spoiler it will create a low pressure area under the car and at the base of the windshield. I have seen leaves, rags and such sucked into the back of the hood at speed. If you are sealed to the hood as I now am you still have the low pressure but not as much. It still should be cooler air. I have a pan from Ramairbox, to seal to the hood. Next iteration, maybe stock?

Its the windshield that creates the large air pressure at speed as witnessed by the air flow through the vents in the car (astro ventilation). the intake for the vents are at the cowl area (grills in the rear hood panel). i elected to open my cowl and block off the air cleaner at the under hood intakes. the outside air pressure at speed has nowhere to go but through the carb. The cool air and the added air pressure induction is free and works really well.


regardless of where you place the air cleaner, if its not sealed from inside the compartment, you are only getting some of the cool air passing through the cowl by the pressure created by the windshield. its still better than pure under hood air.

David Vizard tested intake air temps with a cowl hooded ElCamino or Chevelle. Even with a regular open element non-cowl type air cleaner the intake temps dropped with the cowl hood over non cowl. As I recall there was almost no difference in temps between using the sealed air cleaner and open type but I'd have to go back and re-read it to say for sure. I remember I was kinda surprised at that.

Don't just raise the element, there isn't much benefit from that, I'd get a taller element and longer stud, let it stick up into the hood opening, that's what I did on my 67 Camaro.
David

How about insulating the lower portion of the air cleaner base or pan? Huh, be careful with that longer air cleaner stud.

......As I recall there was almost no difference in temps between using the sealed air cleaner and open type but I'd have to go back and re-read it to say for sure. I remember I was kinda surprised at that.....

That's very interesting. Can you post a link to that article?

thanks

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Does anyone make a pan that will bolt up to the car (under the air filter) and seal around the cowl opening or do you have make one on your own?

I think I saw pics (not sure if it was here or over at pro-touring) of someone who made one out of a large baking pan. Didn't know if something else was available.

Dan, if you dont have the equipment to make your own pan, just buy reproduction stuff. It's just like the factory. (well, allmost) Engine room air never gets used if you cork-up the snorkel. Or you can put a hose on the snorkel and lead it to the front of the engine room under the radiator. It works good for cruising around when not at full throttle.
And Hotrod Magazine, about 35 years ago, said the ducted hood on 69 Camaros was worth 45 horse pressures at 'speed'. They didn't say how they came up with that number.

Look at ramairbox.com #14HS I use this with a K & N 14" x 4" with an X top.

http://www.ramairbox.com/models.html

Someone posted , they used a large deep cake pan for this. You could probably use two , insulate in between?
Probably go step further for race only, apply thin blocks of dry ice above both pans. Some grumption may be needed. The word probably orginated from the word "Grumpy"?

You can get a 14" filter up to 5" tall and still use your drop base air cleaner. I think I've used a 4" or 5" in the past, I don't remember which, but it didn't stick up as far as I thought it would. I now have the K&N with the K&N lid, but will probably go back to a tall paper filter.
I have also seen people stack two air filters. I suppose if you siliconed them together it'd be okay. I'll probably experiment with this in the very near future.
I also have a 1" carb. spacer now, so that'll make a difference too.

David, you mean like this???
http://epitomesrebuild.com/images/138.JPG

David, you mean like this???
http://epitomesrebuild.com/images/138.JPG

Looks trick under that air cleaner!

There's info on my website about how to build your own. Takes about $50 and two hours of fab time.

David, you mean like this???
http://epitomesrebuild.com/images/138.JPG

yeah, but I don't have the factory style air cleaner.

That looks good.

Look at ramairbox.com #14HS I use this with a K & N 14" x 4" with an X top.

http://www.ramairbox.com/models.html

Has anybody actually used one of these filters? I was looking into and made some measurements. It looked like i would need and offset base to clear my small body msd and my coil? If anyone has one installed pistures would be helpful. Thanks.