2000 Honda Insight aero tail extension: made from spare bumper, 5% MPG gain

[aerohead]

Originally Posted by xpedro01

Aerohead--great minds must run in the same gutter. Using ecomodders very good calculater l took standard numbers for the insight + ones l could change, till they matched my before conditions. Then after the installation and testing 4- 18 mile runs, l changed only cd in the info till it matched my mileage for 55MPH with cruise control and 40 degrees(same as before), and it just about agreed with your number. Thanks for verifying.

xpedro01,you're very welcome.This sort of thing is fun for me,and it's a joy to have access to the fruits of others which remind me of all the good work going on out in the world.
I hope one day,that Wolf Hucho will stumble onto EcoModder and get an eyeful of your work,going back to before he got into aero.You've been doing since the 70s,everything he's advocated since the mid-1980s.I think it would be a big kick for him as it is for me.Thanks big-time!

[Superfuelgero]

This could be done cleaner on cars with a sedan counterpart. A civic or metro where the sedan bumper has more rear overhang than the hatchback. Hmmm, another item for the pick a part list....

[California98Civic]

Subscribed!

[benphyr]

I'm being inspired again. Thank you!
Subscribed.

[xpedro01]

MetroMPG--You got it! It was the racing impact.

Benphyr-I am unhappy with the spray can color match. I tried another company and they asked for the 11th digit of the vin number, which tells them about a batch number of the original paint. instead of NH-630M they will be sending NH-630M-T which l hope matches my 2000 silverstone silver lnsight. xpedro01.

[serialk11r]

Nice! I think bumper extension could be fruitful on a lot of sports cars such as mine where the bumper barely pokes past the rear wheels. Adding a couple inches and pushing the edges out I think would create noticable gains. The 911 has a 0.29 drag coefficient vs. the Cayman/Boxster's 0.30 despite a more open bumper, more cooling, and a wider rear track/tires, and I would think that the extra couple of inches has something to do with it. Porsche cars would be hard to modify though, since the body slants downward well past the bottom of the rear hatch.

[xpedro01]

Ron22-I finally got some longer trip numbers. On a trip from Manhattan Kansas to Glen Elder, which is 100 miles on US24, cruise control at 55MPH, (the same as test track) temperature 40 degrees, resulted in a reading of 80.8 MPG. Returning 2 days later-roughly same temperature, when I drove in the yard, l shot the dash at exactly the same number; 80.8 MPG. Now I NEED to run tests at speeds real cars run at.

[MetroMPG]

Nice going, Tom! You make me pine for my Insight.

PS: I see some new modifications:

- plexi-bubble around the side mirror?
- front wheel arch bubble, similar to on your Sprite?

[xpedro01]

June 20, 2015.
My brother in law died and I went to the funeral. The distance is 270 miles, and the altitude in Garden City is 3000 ft; we are 1100+ here in Manhattan. There was no wind & temperature was in the 80's. Cruise control at 55 (Nixon speed) meant all cars passed me. Mpg was 80.6 for 270miles.

On the return trip, I elected to drive at posted speed limits.
US-156 from Garden City to I-70 north of Elsworth is 171 miles.The temp was in the mid 90's and there was a semi favorable breeze. MPG was 78.2 for 171miles at cruise set at 65. This was higher than I expected.

I-70 goes straight east. 65.5 miles at 75 MPH yielded 66.0 MPG. All in all I was very pleased with the Insight. It appears the mod improved mileage. These were ideal conditions, I must admit.

[deejaaa]

Originally Posted by xpedro01

June 20, 2015.
........distance is 270 miles........at 55.....Mpg was 80.6......
posted speed limits.... 171 miles......MPG was 78.2.....cruise set at 65.
....... 65.5 miles at 75 MPH yielded 66.0 MPG............

phenomenal!
am wanting to speed up too on the highway to keep more tailgaters and "change lanes at the last second" people from coming too close.
want to belly pan it using a drop in bed liner. goal is get same mileage at a higher speed.