New lower air dam for 2017 Chevy Full size van

[E.Roy]

Originally Posted by EcoVan

but that does make a lot of sense. I should look back at the NASA studies to see if there is a pattern there.

Any updates on the success of your mod?

I know my 02 Econoline will definitely benefit. Planning on building a rectangular steel tube bumper for protection, but with angled wings and a bottom flange to bolt garden edging that directs air around the outside of front tires.

I did an air dam on my old Civic and it both improved coasting and quieted the wind noise down.

[Tahoe_Hybrid]

I still wondering what the OP did for drive shaft clearance and travel etc.. i don't want to damage mine so so expansive to replace

[E.Roy]

Originally Posted by aerohead

1) Is there any difference between the van and Suburban as far as engine bay air extracting through the front wheel-wells or not ?
2) And could the transmission cooler be affected by a change to the airdam?
3) And does transmission cooling rely to any degree at all on airflow physically sweeping through the transmission tunnel, and directly across the aluminum case as you drive?
4) You may have a full-synthetic lubrication package already, which can handle pretty extreme temperatures, but you'd want to know.

A different perspective, it seems to me that less air dam would tend to increase pressure under the engine bay and body, likely reducing air flow through coolers.

Of course, would need testing to know

[aerohead]

Originally Posted by E.Roy

A different perspective, it seems to me that less air dam would tend to increase pressure under the engine bay and body, likely reducing air flow through coolers.

Of course, would need testing to know

Efficient heat exchanger(s) would harvest the forward stagnation point for the highest pressure source, and it would have to exit, regardless of location, simply because of the delta-P across the heat exchange matrix, as,
anything downstream of the airdam would essentially be at a lower static pressure.
The front wheelhouses are a source of high drag, and the current convention is to fully enclose them, even into the engine bay, allowing air only to escape where deemed appropriate.
Forwards belly paneling would allow for energetic, fully-attached, high-velocity/low-pressure air moving under the engine compartment.

[E.Roy]

Originally Posted by aerohead

Efficient heat exchanger(s) would harvest the forward stagnation point for the highest pressure source, and it would have to exit, regardless of location, simply because of the delta-P across the heat exchange matrix, as,
anything downstream of the airdam would essentially be at a lower static pressure.
The front wheelhouses are a source of high drag, and the current convention is to fully enclose them, even into the engine bay, allowing air only to escape where deemed appropriate.
Forwards belly paneling would allow for energetic, fully-attached, high-velocity/low-pressure air moving under the engine compartment.

I think I want to avoid all the work/issues of paneling the underside of a FULLSIZE VAN by using an air dam to reduce drag.

Whereas you'd want to panel the bottom side and go without an air dam, which could potentially be more effective overall. But I feel the ROI wouldn't be worth it in my case, but I understand you're all in on this stuff.

I propose there's more than 1 area of the vehicle/system to use to extract air from the engine bay, my choice would be not stuffing so much air under, thus keeping pressure low despite some stagnation, and having rear of vehicle/system draw on the engine bay.
I feel it's also possible to increase air speed down sides of vehicle with air dam, which could potentially draw air from engine bay.

[aerohead]

Originally Posted by E.Roy

I think I want to avoid all the work/issues of paneling the underside of a FULLSIZE VAN by using an air dam to reduce drag.

Whereas you'd want to panel the bottom side and go without an air dam, which could potentially be more effective overall. But I feel the ROI wouldn't be worth it in my case, but I understand you're all in on this stuff.

I propose there's more than 1 area of the vehicle/system to use to extract air from the engine bay, my choice would be not stuffing so much air under, thus keeping pressure low despite some stagnation, and having rear of vehicle/system draw on the engine bay.
I feel it's also possible to increase air speed down sides of vehicle with air dam, which could potentially draw air from engine bay.

You'll have to be careful on that. While the back of the vehicle is considered an area of low pressure, it's at a higher pressure than the center of the vehicle, with an opportunity that air at the 'back' will actually flow 'backwards' towards the front.
A belly pan and diffuser makes that impossible.

[freebeard]

Attn: aerohead. Maybe this is the best thread to high-jack.

Recently there was a post [citation needed] about a car that used relatively small high-mounted canard dive planes as vortex generators in front of the wheel well to get similar benefit to an air curtain. Plausible?

[aerohead]

Originally Posted by freebeard

Attn: aerohead. Maybe this is the best thread to high-jack.

Recently there was a post [citation needed] about a car that used relatively small high-mounted canard dive planes as vortex generators in front of the wheel well to get similar benefit to an air curtain. Plausible?

I'm probably not the one to talk to about air curtains.
I'm still advocating for skirts at all wheels, since the automakers still say they're the best solution, drag-wise.
And the $4,000 / hour to develop and 'prove' curtains is kind of a buzz-kill.