Cooling the 6.0 with an Aluminess Bumper

[daveb]

Very interesting. Did you see any cooling difference?

[Millerfish]

Haven't had a chance to test it out yet. I only seem to have cooling issues when on a grade.

[daveb]

I would think it would push air into the engine compartment at high speeds similar to cowl induction. One way to tell how its doin, would be to stick a thermometer in there and run the vehicle at different speeds. I'd be curious if to see if it allows cool air in or if heat is pushed out. Might depends on the speed.

[Millerfish]

I think for it to actually intake air it would need to be raised above the rest of the hood to create a low pressure area between the hood vent and the windshield. Being that there is no interruption of the air flow over the hood and windshield I think it would create a vacuum at the vent and draw air out as the air flows over. I am going to tape a string in the vent and see what the air is doing...

[daveb]

I'll probably try it as well. You're probably right about air going out as cowl induction pushes air into a vacuum (carb) and just the pressure of the air flow through the radiator may be enough to out do what is at the base of the windshield at high speeds. Post back what you find

[Millerfish]

So I did a couple tests with some string and can not really see any significant air flow either way. However at idle and with the engine off there is a lot of heat coming out that gap. So if it's not drawing air in it should not be affecting air air coming through the grill. And it is at the highest part of the engine compartment so some heat will find it's way out of there, so I say it's a good thing... I just can't see the louvered vents doing much more.

[Ford_6L_E350]

I can see the hood vents letting out more air/heat than removing the rubber seal would when moving down the road.

As air moves over the hood it creates a vacuum over the vents (Bernoulli's Principle - faster moving air creates a vacuum), then that same air hits the windshield and creates pressure before it moves up the windshield. The pressure at the windshield is the reason air intake vents are placed there.

Since the engine compartment is pressurized by the air coming in the radiator there may be very little pressure differential at the base of the windshield and little or no airflow out from under the hood.

But, a vacuum above and pressure below the vents could cause significant air flow through the vents. However it may mean that the interior vents draw in that heated air, forcing use of AC and negating any benefits.

Mike

[Millerfish]

From the tests I am pretty sure the vent is not drawing air in. The strings did indicate some exhaust of air just very little. I think the rear of the hood is far enough away from the windshield to be out of the high pressure area created. Also the angle between the hood and windshield is not very significant further decreasing the pressure. I would like to see some sort of test to on the hood vents to see the amount of air flow.

[daveb]

But that is a good point Mike made. I was hoping windshield pressure would force air down but here in sunny Ca I'm more worried about hot air entering the cowl ducts causing A/C issues. Didn't even think of that. When I need the coolest air coming into the ducts is at idle and low speeds. So being 100+ degrees is common here, I'm gonna pass on removing the strip. I called about the vents Herb posted about yesterday and plan on getting them headed my way. When I off roaded with Jeff (myriadmyriad) he also had the vents plus fans mounted under them. He claimed it made a huge difference.

[BroncoHauler]

Here's what some Bronco guys run, inner fender vents. Probably not the best idea if wheeling in mud, but it's idea that I don't think has been tried on a van.


http://www.wildhorses4x4.com/product/Ve ... nder_Vents


Herb