Cowl Induction Hoods (functional), Good OR Bad?

[john8662]

I have stumbled upon a great deal for a steel functional cowl induction hood that will fit my 95 K2500 suburban. I have noticed that the under-the-hood temps are really high, after a warm drive in 100 degree temps you can't touch anything under the hood, either connected or disconnected from the actual engine. The hood I am considering is a 3" functional cowl hood that is only opened at the end towards the windshield.

So, who has one installed, and is this going to make any difference in the cooling, besides the cool look factor? I am not having ANY cooling problems with coolant temps whatsoever, but I just want to get under hood temps down. I also wonder if there are any bad affects as a result of this. I have search the forum and haven't turned up much on the subject specifically to the hood. Thanks!

[Turbine Doc]

John,

RATDOC had one on his Burb before he traded it on a DMAX, said it was very successful for lowering underhood temps on his, one of the mods yet to do on mine, beside I think it looks cool what kindf of deal you find on one when I 1st started looking they were about $400 + shipping. This the GoodMark hood or another brand, I've found glass ones for less but I want steel

[john8662]

Tim,

I know a guy that has one installed on his 2wd 98 gas suburban, he is trading his burb in, the hood is still primer color, he never painted it. He said I could have it for around 150. Yeah, they are sure expensive outright, plus freight to get it, so I never did get one.

[catmandoo]

i'm running a 2 scoop hood similar to the old 70 olds 442.it dumps out right behind the pass battery and i still need to make an air box so i can suck totally off the hood.but until then i've even noticed the temps down some on really hot days.

[ttpost]

oringinallly on the camaros they were used to induce cold air into the air cleaner, for more performance. they actually were more of a ram air system. but with aerodynamics of the truck i am sure they would work great.
i would like them to be outlawed on anything but a chevy though, especially on fords :D :D

[More Power]

If plumbed into the air intake system of the vehicle, a cowl induction hood can produce a significant benefit.

If the cowl air is dumped into the engine compartment, engine cooling could suffer.

Air moves through the grille mounted coolers (oil coolers, AC condenser, radiator, etc.) because of a difference in air pressure front to back. Dumping air into the engine compartment from anywhere other than through the grille works to equalize the air pressure, and could interfere with the airflow through the radiator etc.

Theory aside, the 6.5 Project truck doesn't seem to suffer by having a cowl induction hood that isn't plumbed into the air intake.... But, I'd like to know what improvements there might be if it was plumbed properly.

In the end, most install A CI hood for the appearance.....

MP

[john8662]

Excellent, I'll go pick it up and find a painter to match it to my green exterior color. I just didn't want to put something on it that would sacrafice cooling, because thats a department that these 6.5ers need the most, good cooling. Thanks for the input.

[rjwest]

What happens when Large amounts of water is ingested into the engine from a cowl intake....
do you need a water trap?

[catmandoo]

thats one thing i have been contemplating.some sort of a deflector in the top of my air box to funnel the water away as mine sucks right off the front of the hood the other day in a driving rain it would have sucked in gallons if i would have had an airbox made.

[patrick m.]

i have a cowl hood, and when driving in the rain, i can watch the water drip off of the back of the hood, and on to the winshield.
Mine is not plumbed into the air box (yet), so i cant say that no water finds its way into the ducting, but it doesnt appear to.

[TJ]

I am looking for a cowl hood for my 98. Does anybody know the best place to purchase?

[catmandoo]

i got my hood from stylinconcepts.com

[Uncle Wally]

Theory for thought:

As the air passes over the car, a high pressure pocket is created at the base of the windshield. This is more prominant on vehicles with a windshield that is more verticle than others. When Chevrolet came out with the Cowl Induction Hood design, it was to take advantage of that high pressure pocket. Not only does that air act like a big ram air scoop that faces forward, the air in that pocket is much cooler. It hasn't been through the cooling systems. Hence the air is more dense. As we already know, the denser the air, more power is available (at least in the diesel world). Just as More Power stated, the differential pressure across the radiator is less if the CI Hood is not plumbed into the intake tract, making a potential problem with limited cooling due to less flow through the radiator etc. The flip side, the air is not moving through the radiator as fast, so on cool days, it has the potential to remove more heat from the radiator. Kind of a two edged sword. Both good and bad.

Waldo