Truck Aerodynamics - cost effective mods?

[Blu3Z3rg]

Hi guys!
First posting on these forums, but i've been reading them a good bit last couple years!
I currently have a GAS HOG. 2005 Dodge Dakota Quad Cab V8 4x4. I use EVERY aspect of this truck to it's fullest and my only other option really was to go with a full size truck, but they were all a good $5-10k more than I bought this when I have the 4x4 and quad cab. I'm not here to argue about my vehicle choice... only to make it better!!!
I have a thread on a dodge forums that follows my progress of moving up from 15 mpg, but i can't link it yet - i will when I have more than 5 posts!

As for my FIRST aero mods, I'm looking at an air dam/chin spoiler, BUT, I wonder if a belly-pan would be more effective?
Air dam would lessen the air under the truck, but the belly pan would smooth it out.
The first part of the pan I would do would only be the first 2 feet under the front of the truck, so would it be worth it compared to the air dam?

Ok, and after I do that.... I need a next aero mod!!!!!
Blu3

[FastPlastic]

If you get any kind of snow in your area I would recommend a decent belly pan. The extra clearance has come in handy for me.

[Blu3Z3rg]

Originally Posted by FastPlastic

If you get any kind of snow in your area I would recommend a decent belly pan. The extra clearance has come in handy for me.

That's a good point! I do get a good bit of snow, which is part of the reason i NEED the 4x4. When it snows, i need to get to the shop and get the trucks out the door. I also have to go to all of our construction sites and check everything to make sure everything is ok. Also, mud can really ruin my day, and I have to say, this Dodge's 4x4 is AWESOME for tackling these tasks.

Perhaps I would make a small air dam in order to reach down to where the cross-member is. Currently, the bumper is about 4" higher than the cross-member, which is really a bad design.

I wonder how to design a belly-pan in order to still have access to the oil filter though? I'd like the pan to go to the cross-member that I am refering too, but it will get int he way of the filter.... hrrrmmmmmmm

[Joenavy85]

i would say get a slanted bed cover, it would still allow you to use a majority of the space back there. if you don't have the tow hooks on the front you can get a couple small pieces of plexiglass to put over the holes for them, as well as the fog lights to smooth out the air flow. also you could cover the top half of the grille opening with lexan (to keep the look clean), when you do that also go under the hood and fill any gaps that could allow air to flow around the radiator rather than through it.

[Frank Lee]

I would say if you've been reading these forums for several years already, that you'd have a good idea of what to do.

[Blu3Z3rg]

Originally Posted by Frank Lee

I would say if you've been reading these forums for several years already, that you'd have a good idea of what to do.

Very true!!!
I guess I was hopeing some genious had done wind tunnel testing on my truck to see what was more effective, an air dam, or a belly pan....

that may be possible with a mock-up toy test or something.... there's little places on the truck all over that i find could be improved whenever it snows and i drive in it a while... it's like a free wind tunnel test cuz wherever the snow stays is low pressure. I usually end up with a pile behind my rear window, for example, but it's interesting to see where the snow comes to a point from the sides of the cab as well. It really looks like an "aero" cap would only have to angle out like 2-3 feet into the bed to be fully effective.

[Joenavy85]

Originally Posted by Blu3Z3rg

I wonder how to design a belly-pan in order to still have access to the oil filter though? I'd like the pan to go to the cross-member that I am refering too, but it will get int he way of the filter.... hrrrmmmmmmm

i have a pan that blocks access to the filter, i just have a removable piece of coroplast held in place by a couple plastic tabs that rotate to hold it place (like the back piece on a picture frame)

[Joenavy85]

Originally Posted by Blu3Z3rg

It really looks like an "aero" cap would only have to angle out like 2-3 feet into the bed to be fully effective.

a full bed cap would be the best because of the down angle, and depending on the angle you could help out with a couple vortex generators to maintain air flow attachment on the way down the back

[Joenavy85]

Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - aerohead's Album: Pickup images check out aerohead's truck, this should give you an idea

[fjasper]

Originally Posted by Joenavy85

a full bed cap would be the best because of the down angle, and depending on the angle you could help out with a couple vortex generators to maintain air flow attachment on the way down the back

Aaaaaaaaaaaaahhhhhhhhhhhhhh!!!!!!!!!NO, DON'T BRING UP VORTEX GENERATORS!!!!!!!!! NOT AGAIN, I CAN'T TAKE IT ANY MORE!!!!!!!!!!!

Just kidding. If you deal with sticky mud, make sure the belly pan can handle it. Either set it up so that mud can't get up on top of it and pull it down, or make it fairly tough and easy to clean, or all three.

Coroplast seems like it might be good for inner fender liners to keep mud off the underside of the rig. It's flexible enough that dried mud should break off fairly easily, helping reduce the weight gain you get when you're in the mud.

That's a nice-looking cap, by the way.