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Cowl hood or Ram air?
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Posted by: JoeBlow

Some one told me that a cowl hood will move more air than ram air induction, and that a cowl hood's air temp. is slightly lower than a ram air setup.

If any one has information on this topic it would be nice to here what you think, I'm trying to make a choice on air induction for my car.

Posted by: LS1JAY

BS! If it's a functional "ram air" set up, no cowl hood in the world will get more air to your motor!

Posted by: JoeBlow

It could very well be B.S. I read about a test on some web site, that claimed that cowl hoods have larger out-let's & thus moved more air. They said the ram air inlet's are just smaller.

I dont think that they tested all of the diffrent kinds of ram air set up's either. And the cowl hood was only a 4 inch rise, Ive heard of 7 and 9 inch rise cowl hoods.

I guess in the end I like both set up's and I will have to do an independant test, to see what works best for my car. I believe a fast car depends on the right combination of parts that work best together.

Posted by: LS1JAY

Ram air force feeds cold air directly to the engine, a cowl hood simply helps get the air out, but doesn't force feed it fresh cold air like a functional ram air does. I'm speaking from experience and not some magazine BS test.

Posted by: JoeBlow

"Experience"

I have used ram air set ups on my car. I used ducting hooked from the sides of my radiator back to a dual inlet snorkel. It worked well and It seemed to improve performance. I think a ram air scoop would move more air.
I really dont like the ducting above my engine, and dont really want to cut a hole in my hood. But then thiers the cost diffrence, with the high prices for cowl hoods.

Posted by: LS1JAY

Every ram air/cold air induction system I have ever used, was from underneath. I had the factory SS hood on my SS (of course), but I also did the Free Ram Air mod from underneath and picked up 1/10 and 1 mph in the 1/8th mile alone!

Posted by: JoeBlow

Those kind of setup's seem to work well. I might turn my dual air inlet, into a single snorkel inlet, for up coming cold weather. It's seem's to be much harder, to start my car in the winter.

Posted by: LS1JAY

So what kind of car do you have?

Posted by: MadScientistMatt

Quote:

Originally Posted by LS1JAY


	Ram air force feeds cold air directly to the engine, a cowl hood simply helps get the air out, but doesn't force feed it fresh cold air like a functional ram air does. I'm speaking from experience and not some magazine BS test.

My experience is a little bit different. My Dart doesn't have a cowl hood, but it does have a set of vents at the cowl connected to air vents in the interior. There isn't any fan in this ventilation system anywhere, but open the vents and you'll get a very intense stream of air into the cabin, driven only by the air pressure at the cowl. Cowl vents can most certainly force cold air into an intake, just as easily as they can force it into the passenger compartment.

The sharp turn the air has to make at the base of the windshield creates a high pressure area. This will drive the air down any opening in that area, whether it's a cowl hood or vents like my Dart has.

On the other hand, this effect probably isn't going to be as big with a steeply raked windshield, like on a fourth generation F-body. You'd need a lot of windshield rake for a cowl hood to pull air out of the engine compartment.

Posted by: JoeBlow

A hood with vents to the air intke sounds like a nice setup. I believe a cowl, or vented hood does cause a good deal of air pressure. I dont know if it is greater than a ram air scoop, because of the higher level of air concentration caused by the scoop. Their is a drag that scoops will cause because their not aerodynamic, some are better designed.

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