Great success with airdam on '98 Odyssey

[westygo]

I recently bought a great condition '98 Odyssey with 120,000 km on it. Great van, but wow, the underbody is absolutely horrible '
I bought a 6" strip of ABS, cut and drilled and bent and installed and have achieved a 16% improvement in fuel efficiency on the highway! This has paid for itself in a tank and a half of gas!
Pics to follow!

[westygo]

I simply used the factory attachment points, drilled holes at the bend points to eliminate the possibility of cracking and bolted in place. I bent the ends out to deflect flow around the front tires. Looks almost invisible, but does scrape parking curbs a bit.

[westygo]

This is how ugly the underside is!

[westygo]

Next steps will be upper grille block, seal gaps and block off the edges of the lower grille that are not directly in front of the radiator. Also may add a belly pan up front that will shoot a bit past the dam and act as a splitter. This will allow spats in front of the front wheels.
So much potential on this great van!

[freebeard]

Nice work. Did you heat the ends to get them to hold the bend?

It will be interesting to see if the 16% holds up over time. Sometimes barometric pressure and other things can affect mileage in the short term.

[Gasoline Fumes]

Nice job, looks great! My parents have a '97, rebadged by Isuzu. I had a splitter on it for a while, but it eventually fell apart. I agree, the undersides of these vans are really bad!

[kach22i]

Originally Posted by freebeard

Nice work.

Did you heat the ends to get them to hold the bend?

Those were my first two thoughts as well.

The material fatigue of bending without heat would be too much in the long term I suspect.

Super clean installation, professional looking.

I still favor my conveyor belt material, it has flexed when pulling off of parking curbs. Just a tiny bit on one corner caught a few times, but a harder material would have stressed out and maybe failed by now.

[westygo]

Thanks guys.
All bends are heat bent. The drill holes will go a long way to prevent cracking, and ABS is highly impact resistant, but not like conveyor belt.
Trying to follow the 80/20 rule and stick to big wins on this one, but it is tempting to go whole hog and belly pan the whole thing. Fortunately time is a big limiting factor. :-)

[MetroMPG]

Nice work, westygo!

How did you calculate the percent improvement?

Also: you must have one of the lowest post frequencies around here. (Join date June 2009! ) But you make up for the lack of volume with quality.

[westygo]

Thanks Metro MPG for the compliments.
Nope, I don't post much :-)
I keep tabs on every tank. Prior to installing the air dam, my best tank ever was 9.8 L/100km on a road trip. I repeated the road trip with the same cargo and same two bikes on the back same driving style same weather etc, and achieved 8.2 L/100km. Pretty sure that works out to a 16.4% difference.