Jeep Cherokee Aeromods - Page 6 - Fuel Economy, Hypermiling, EcoModding News and Forum

FastPlastic · 07-11-2008, 04:05 PM

Quote:

Originally Posted by Red

Cool, I'd say see if you could extend it a bit more towards the bottom of the axle tube since it seems like you are still getting some flow over and above the axle

Ok so I ran a few more tests and found that making it longer did help a little getting it under the axle. But I found adding a lip at the end seems to make the biggest difference. Plus I think adding the lip would help strengthen the trailing edge of my panel as well.

Thanks for the help.
Phil

Red · 07-11-2008, 05:54 PM

Sweet

FastPlastic · 07-14-2008, 01:29 PM

Ok, this is a little off topic. But I was wonder if anyone knew if a 1998 Jeep Cherokee has what I've heard of "Fuel Cut Off"? When your coasting down a hill it shuts off the fuel flow. I don't have a scan gauge so I don't know if it does or not. The reason I'm asking is the last tank of gas I tried just driving with out shifting to neutral. Turns out I got better gas mileage then I've gotten using the N shifting.

DoctorP82 · 07-14-2008, 06:35 PM

Quote:

Originally Posted by FastPlastic

Ok, this is a little off topic. But I was wonder if anyone knew if a 1998 Jeep Cherokee has what I've heard of "Fuel Cut Off"? When your coasting down a hill it shuts off the fuel flow. I don't have a scan gauge so I don't know if it does or not. The reason I'm asking is the last tank of gas I tried just driving with out shifting to neutral. Turns out I got better gas mileage then I've gotten using the N shifting.

If someone figures this out, I'd like to know the source so I could investigate on my '93 Cherokee as well.

FP - where do you find this Flow Illustrator? Looks useful, and I'd love to put it to work for me. Also, the skid guard looks good, is this going to be with the air dam as well?

FastPlastic · 07-15-2008, 11:52 AM

Quote:

Originally Posted by DoctorP82

FP - where do you find this Flow Illustrator? Looks useful, and I'd love to put it to work for me. Also, the skid guard looks good, is this going to be with the air dam as well?

The flow illustrator is thanks to thirdman who posted the link to the app here. It's nothing special but it gives you an idea of what's happening.

As for the air dam. For now I'm going to forgo building it. I do mostly in town driving and the design idea I had to keep ground clearance would require dropping it down for highway driving. So I decided to work on the skid plate instead. Smoothing the airflow under the vehicle without dropping my clearance.

Tony Raine · 07-15-2008, 01:07 PM

Quote:

Any suggestions on what to make it out of?

i'm hearing more and more about rock-crawlers using "cutting board" material for their skidplates. light, strong, and slick. apparently you can get the stuff in bigger sheets in various thickness. i think the offroad guys use 1/4" or 1/2", but i bet it comes in thinner pieces.

for the "lip" at the end, cut a strip about an inch wide, the length of the skidplate, with a saw set at 45 degrees. glue/screw it on, and theres your deflector/brace. (you could add more than 1 layer if you wanted to go farther down)

FastPlastic · 07-18-2008, 03:48 AM

Picked up a sheet of Galvanized steel today (well yesterday now). Only cost $7 for a 24x36in sheet. Sadly they didn't have any long enough so I'm going to have to put a seam down the middle. Not that big a deal seeing as I was going to reinforce it in places anyway. I'll see about posting pics when I get it started.

almightybmw · 07-18-2008, 04:02 AM

Quote:

Originally Posted by Tony Raine

i'm hearing more and more about rock-crawlers using "cutting board" material for their skidplates. light, strong, and slick. apparently you can get the stuff in bigger sheets in various thickness. i think the offroad guys use 1/4" or 1/2", but i bet it comes in thinner pieces.

for the "lip" at the end, cut a strip about an inch wide, the length of the skidplate, with a saw set at 45 degrees. glue/screw it on, and theres your deflector/brace. (you could add more than 1 layer if you wanted to go farther down)

Ultra High Molecular Weight Polyethylene (UHMW-PE) is what you're thinking of. Used all over the place where strength and slippery go together. Awesome stuff, but expensive. You can get 1/8" 4'x8' sheets. I place to do that someday and just cut to fit the underside.

FastPlastic · 07-23-2008, 02:26 PM

Ordered my ScanGaugeII today!!! I'm excited if you can't tell. Ebay is running a special that you can get 10% off any purchase if you use Paypal. Which tipped the scales for me on weather or not I should get one. Saved me $16 bringing the total cost to $143.95. If anyones interested the code is CJULYFUN0810P. It's good till the 29th of July, so if your interested you might want to pick one up soon.

Can't wait to really do some testing to see what improvements work the best!

FastPlastic · 07-24-2008, 05:39 PM

Ok had some more time to work on the skid plate. Turns out my 2000 pound epoxy doesn't want to stick to the galvanized steel. So I switched to using pop rivets instead. Got the two peices connected together (needed 37" the sheet was only 36". Grr) and all of the cutting and bending done. I plan on putting in a few more pop rivets along the bottom edge to strengthen the panel up a little bit more (plus I like the looks of them). Then about all thats left is the final mounting.