Jeep Cherokee Aeromods

[oisiaa]

Great thread!

I have a 2001 stock Cherokee. I live in a dormitory so I don't have access to a garage to screw around very much. I'll probably remove the roof rack since it is a simple start. Unfortunately my average speed is ~20mph so any aerodynamic mods will result in negligible gains.

I'll definitely keep an eye on this thread.

[winkosmosis]

Found some Cherokee tuft testing that a guy did to figure out where to add hood vents. He found that pressure is pretty low at the front of the hood... so you could potentially reduce drag by putting vents there

Bonnet

[FastPlastic]

Originally Posted by oisiaa

Great thread!

I have a 2001 stock Cherokee. I live in a dormitory so I don't have access to a garage to screw around very much. I'll probably remove the roof rack since it is a simple start. Unfortunately my average speed is ~20mph so any aerodynamic mods will result in negligible gains.

I'll definitely keep an eye on this thread.

Watch those tire pressures. A very simple thing that can make a big difference, no matter what the speed.

Originally Posted by winkosmosis

Found some Cherokee tuft testing that a guy did to figure out where to add hood vents. He found that pressure is pretty low at the front of the hood... so you could potentially reduce drag by putting vents there

Bonnet

Tempting, but I'm not too prone to cutting holes in my car.

[winkosmosis]

Do you have a plastic/rubber splash guard? I didn't think there was one available for the XJ but apparently there is. Found out because I was searching for info on front hitches conflicting with skid plates

Front hitch or tow hooks question - [Archive] - ILOVEJEEPS.com Forums

the splash guard will help to reduce the amount of spalsh into/onto the alternator (and other under hood, but the alt seems to benefit most) ... you can live fine without it, though you may notice:

slightly decreased high-speed cooling (less negative pressure behind the radiator and more of a propencity for the high-pressure area in front of the front diff to reduce air flow
more of the classic "mud/brush" conflict with the alternator (the alt hates to get wet or fouled with mud - it'll float a brush pretty easily - just carry some clear water to rinse-off the back )
Decreased heater output on really cold days (the flappy thing actually diverts really cold air off of the oil pan, running with and without it on one of my '87s made a huge difference in cab comfort when outside was below roughly 10*F)
Decreased water fording depth (again the pressure things - slow-speed fording depth will be reduced since you'll be less able to build and hold a good bow-wave


Really though -- all of those things are really minor, and about the only thing you may see is that your alternator will be a bit more prone to fouling and maybe a little drop in fuel economy (will a factory or other front skid plate fit on with that hitch mount? that'd clear all the stuff up.)

[FastPlastic]

Originally Posted by winkosmosis

Do you have a plastic/rubber splash guard?

I do, but it's starting to fall apart in a few places. The new front skid plate pretty much takes it's place keeping water/mud off the front engine compartment.

[winkosmosis]

You got a skid plate? The OEM one?

I'm looking for an OEM but can't find them for sale anywhere. The aftermarket ones are probably heavy, because they're thick plate instead of thin sheet with ridges for strength

[FastPlastic]

Originally Posted by winkosmosis

You got a skid plate? The OEM one?

I'm looking for an OEM but can't find them for sale anywhere. The aftermarket ones are probably heavy, because they're thick plate instead of thin sheet with ridges for strength

Yes and no. It's part of my under body tray. My design splits it up in to different sections similar to what the off road Jeeps have. Which I guess is why I call it a skid plate. By no means should you put the weight of the Jeep on these. They are galvanized steel used for home heating air ducts. So each panel weighs about 3 pounds. Check back a few pages on my post to see what I'm talking about.

[winkosmosis]

Originally Posted by FastPlastic

Yes and no. It's part of my under body tray. My design splits it up in to different sections similar to what the off road Jeeps have. Which I guess is why I call it a skid plate. By no means should you put the weight of the Jeep on these. They are galvanized steel used for home heating air ducts. So each panel weighs about 3 pounds. Check back a few pages on my post to see what I'm talking about.

Ah OK, I missed those posts. I didn't realize you had the belly pans

[winkosmosis]

I have another idea-- cover the headlamp buckets with clear plastic. I realized while half asleep in bed, that this could have a HUGE effect, because not only would the flow be much smoother, but it would then stay attached as it hits the radiused corners of the front end.

I've found that the unpainted black buckets go for about $20 on eBay, so I'll probably try this at some point. Don't want to drill into my color matched painted stock ones.


Ordered a front skid too... Found them for only $52+$9 shipping
In case anyone wants these, part # 82202851 at http://www.moparpartsamerica.com/

[FastPlastic]

Originally Posted by winkosmosis

I have another idea-- cover the headlamp buckets with clear plastic. I realized while half asleep in bed, that this could have a HUGE effect, because not only would the flow be much smoother, but it would then stay attached as it hits the radiused corners of the front end.

I've found that the unpainted black buckets go for about $20 on eBay, so I'll probably try this at some point. Don't want to drill into my color matched painted stock ones.

Check the laws concerning headlights in your state. Some have rules about not covering the headlights.

I have been tempted to at least seal the gap around the headlights. Having the pressure zone in the front would be better then the air headed in the messy engine compartment.