first results

[kitcar]

I just did a test loop (25 miles, 12 mi. east, 13 mi. south) today with the new air dam, side skirts and grill blockers. My max. speed on the highway is 65 mph, 70 mph for passing. Air temp. is 68 degrees, 24% humidity, winds 6-10 mph variable.

The basics:
Stock city: 19.2, highway 20.1 (bed cover, no acetone in gas), coolant 185.

Last year: city: 19.5, highway 22.5-23.0 (air dam, bed cover, grill inserts, 8 oz acetone/20 gallons), coolant 195, 210 in stop and go. Instant mileage read 23-24 mpg.

This year (today): city: 20.5, highway 26.4 (air dam, side skirts, grill blocker, grill inserts, bed cover, 8 oz acetone/20 gallons), coolant 195, 220 in stop and go. Instant mileage reads 25 - 28 mpg.

Video of mods here:

Next weekend will tell when I drive to the cabin (247.9 miles each way). Best average mileage to date was 23.0. With the electric fans (the Dodge Dakota with the 4.7 has a mechanical clutch fan and an electric fan) the temp. without the blockers would stay at 190 in stop and go. We'll see how they work out in 90 degree weather.

My plan (barring rainy weather) next weekend is to pull the wipers and fold in the passenger side mirror as well.

[kitcar]

One other item to add to the mod list; AirRaid cone filter inserted into the passenger side fender.

[Hockey4mnhs]

add yourself to the garage!!! and make a gas log

[thisisntjared]

Originally Posted by Hockey4mnhs

add yourself to the garage!!! and make a gas log

[kitcar]

I did yesterday afternoon. Haven't added any documentation as yet.

I have to drive some this afternoon and will do another driving loop. Since I need to replace my serpentine belt this morning, I'm going to grab some silicone adhesive and mount those pesky cab spoilers. I'm convinced the stylish radius at the back of the cab is the cause of the buffeting in the bed.

Video to follow.

[kitcar]

Second test following the same driving loop I use for mileage tests, 25 miles highway (east, then south, off the highway, north then west). Before the new mods, 19.5 best for this loop, 22 if there was no wind, etc.. Also did a city loop (8 stops, 10 miles one way, speeds range from 25 - 50 mph) as well, resetting the overhead. City is 23 mpg from a cold engine start through full engine temp.. Old was 21.5 at best.

Friday, 64 degrees, no wind, 20% humidity, all highway; 26.59 mpg @ 65 mph

Today, 63 degrees, winds 9 mph (north) gusts to 20, 78% humidity, all highway. Side wind 50% of highway, tail wind 25%, head wind 25%. Highest mileage, 32 mpg at 65 mph with tail wind. Lowest 21 with head wind. Average came to 23.4 @ 65 mph or 3.9 mpg over previous in this type of condition.

The cab spoilers, btw had no effect on the bed cover. I'm wondering if they're actually hurting the mileage.

[MnFocus]

Originally Posted by kitcar

The cab spoilers, btw had no effect on the bed cover. I'm wondering if they're actually hurting the mileage.

In my eyes , Yes they probably are affecting FE .
Also To my untrained eye the cab spoilers stick up too high and do not extend far enough rearward . From what I recall the cab slip stream is to be extended further back to alleviate the bed cover buffeting ? If so extend them @ 1' ala cab extender .

[kitcar]

Well, you are a mind reading Einstein! After I posted, I put them back at almost 90 degrees. Just heat them babies up and adjust the angle. The idea seems like it would work but needs fine tuning. Having the gap at the cyclops might not have the effect I was hoping for. I'm almost thinking tilting them down towards the bed would actually be better.

[MnFocus]

True dat on the 3 rd brake light gap ! I'd find a way to do a full width with the rear edge of the cab sides included . I'd think that 10-15* shy of a 90* would be enough to achieve reduced buffeting w/o much increase in drag .
(thanks on the Einstein compliment too Hahahaha *wink wink*)

[kitcar]

The other point I forgot is that I'm also testing the load that I take to the cabin; I put the battery bank (couple hundred pounds) in the bed before todays test. I'll also be having 10 gallons of water, additional 5 gallons of gas and some misc. crap so figure 300 extra lbs.

I also noticed that it takes a looooong time to coast down at highway speeds.

I'm going to eliminate the gap over the cyclops later this week. I might try to use a fastener system and have everything pre-drilled and stop at a rest stop and put it on for some on the road testing.