[sad-lumina-owner]

http://ecomodder.com/forum/showthrea...prius-587.html

From the Australian web magazine Autospeed -

Some of you may have seen these already...

Modifying Under-Car Airflow, Part 1

Modifying Under-Car Airflow, Part 2

Originally these articles used to be pay-access only, but they've opened them up for public access now.

The project documents the creation of a prototype front partial undertray for a 1st gen Prius, testing, and then fabrication of a permanent version.

Before:



Mockup:



Final version:



The writer reports a 10+% improvement in fuel economy at freeway speeds (100km/h) with the mod in place. I frankly find that a bit difficult to believe, though I don't doubt there was some improvement.

If you read the article you can find a few holes in his testing approach - even though he's fairly aware of things like experimenter bias, and aiming to perform tests on the same day (for consistent weather conditions).

The articles also give a good background on the subject of under car aerodynamics. Definitely worth a read if you haven't seen them yet:

So Im wondering if anyone has done any mods like this to the Lumina, and if so, what MPG savings did you achieve?