New member, old hand

kitcar · 05-16-2007, 04:10 PM

Hi everyone! I host a video on demand show that details alternative energy as well as increasing gas mileage. I started a new episode tonight about aero mods and during one of my many searches found this site. Imagine my surprise.

Part of the show is filmed at my cabin which is about 250 miles one way, so gas mileage is pretty important.

Anyways, I've started with a '99 Dodge Dakota with a 3.8 V6. I got that truck up to 22.9 on the highway or 5/8 of a tank each way.

Now I've got a 2k Dakota with a 4.7 V8. I now have this truck at the exact same mileage as the 3.8, 22.9 on the highway, 21.5 city.

My goal is 25 mpg on the highway which translates to 1/2 tank each way. That would be sweet now that gas is approaching 3.50 a gallon here in SE Michigan.

Tonight I added (in addition to a partially closed grill, front air dam and bed cover) side skirts with a flair at the rear wheels. Of course all my mods are home brew. My next project is moving the high pressure area that slams on the bed cover at the tailgate 2 feet back behind the tailgate. You should see the bed cover; it's ripped up at the tailgate.

If you guys are interested, I can post video/photos of the mods.

Max

Hockey4mnhs · 05-16-2007, 04:16 PM

be sure to add your truck to the garage and start a gas log. my friend has that same truck with some mods im trying to get him to hypermile but its only on occation that he does if and when you get that mileage (you can) it will be great to show him.

Oh and post the the video and or pics if you can

kitcar · 05-16-2007, 04:29 PM

I don't have the episode about the mileage done; just started shooting tonight. Each episode takes about 3 weeks. Since my publisher doesn't demand a tight schedule, I can take my time on each show. That way it's especially stupid once I add the beer.

I'll see if I can grab some of video and post it. The side skirts don't look TOO bad. You can see the screw heads but I did them the same color as the truck (black).

I'll get right on a quickie video short. Might get it done tonight.

Max

red91sit · 05-16-2007, 05:20 PM

Quote:

Originally Posted by kitcar

Hi everyone! I host a video on demand show that details alternative energy as well as increasing gas mileage. I started a new episode tonight about aero mods and during one of my many searches found this site. Imagine my surprise.

Part of the show is filmed at my cabin which is about 250 miles one way, so gas mileage is pretty important.

Anyways, I've started with a '99 Dodge Dakota with a 3.8 V6. I got that truck up to 22.9 on the highway or 5/8 of a tank each way.

Now I've got a 2k Dakota with a 4.7 V8. I now have this truck at the exact same mileage as the 3.8, 22.9 on the highway, 21.5 city.

My goal is 25 mpg on the highway which translates to 1/2 tank each way. That would be sweet now that gas is approaching 3.50 a gallon here in SE Michigan.

Tonight I added (in addition to a partially closed grill, front air dam and bed cover) side skirts with a flair at the rear wheels. Of course all my mods are home brew. My next project is moving the high pressure area that slams on the bed cover at the tailgate 2 feet back behind the tailgate. You should see the bed cover; it's ripped up at the tailgate.

If you guys are interested, I can post video/photos of the mods.

Max

Welcome to the sight! I dont' think you will have any troubles reaching your goals once you develop your driving style a little better, and perhaps some more aerodynamic modifications.

I would be guessing that the cause of the torn toneau cover is buffeting. Have you considered a full on bed cap? This would be a very big help to your vehicles aerodynamics.

kitcar · 05-16-2007, 05:32 PM

No cap, too much weight. One problem that presents itself is that I move one of my battery banks back and forth to the cabin - that adds 190 pounds by itself. That's one of the primary reasons why I have a regular cab, short bed. We can move the buffet back with the addition a small spoiler to the rear edge of the cab. I did some studying of the problem. An addition of a 1/2 inch 90 degree flat edge above the flow above the rear radius of the cab should solve the problem. This particular truck has a radius at the rear of the cab that appears to cause the airflow to dip into the bed. I think that the 1/2 inch will not add enough areo resistance to offset changing the pressure gradient onto the cover. I'm adding the strings to the cover this weekend to study the problem further. My current plan is to add the edge and drive with the strings attached at highway speeds. Worth the gas for the results.

Max

MetroMPG · 05-16-2007, 05:47 PM

Quote:

Originally Posted by kitcar

No cap, too much weight.

The benefits of an aeroshell on the back will more than make up for the weight penalty, unless all your driving is stop & go, sub 25 mph. You've seen Phil Knox's truck, yes?

Welcome to the site!

kitcar · 05-16-2007, 06:13 PM

5 days out of the week is city. See, I live 9 miles from work. I'll video tape it tomorrow morning. My max. speed on the weekdays is 45 mph.

Moving extra mass up to speed is too much of a weight penalty. Power:weight. There are times that I need to get to speed now. I don't need dead weight holding me back.

Don't forget Michigan is the land of orange barrels. Stop, go, watch the idiots fly by to the end of the lane. Move in front of them with the semi's to block them. They're learning. Slowly. Even the highway can be stop and go.

Now if we can get a shell that comes in under a 100 pounds, that might tickle my fancy.

End result is don't bother trying to sell me on a cap/shell. Less weight requires less power to move to speed and keep it there. Let's move the air around instead. The top of these trucks is darned good. All I need to do is move the pressure back 2 feet. We can do this without a cap.

Max

omgwtfbyobbq · 05-16-2007, 07:11 PM

Al. It's 'spensive, but light. 100-200lbs in a ~4500lb truck will only decrease off the line acceleration by ~2-4%, and if it drops Cd enough, will improve acceleration by more than that at higher speeds.

edit- What about a wood frame with a button up tarp? That'd weight maybe 30lbs and be cheaper'n dirt.