[aerohead]

Originally Posted by Istas

Aerohead: Thanks for bringing that to my attention.

You're using this calculator, here? Aerodynamic & rolling resistance, power & MPG calculator - EcoModder.com

I put my car's Cd (0.33) and weight (2830, plus 200 pounds for the driver) in there, along with the original area (20.63 sq ft), as well as the rolling resistance measurement I got last week (0.0103, I'll be re-doing this to check), then dropped the engine efficiency to .21 to bring the numbers more in line with my experienced fuel mileage. (derived by fill-the-tank-and-calculate, but better than nothing)

Using that as a baseline, it spits out 35.96 mpg at 60mph (my preferred compromise highway speed). When I drop the area to 20.13 (which is what it is after passenger mirror removal and driver mirror fold-in), and plug in a Cd of 0.23, the calculator spits out a fuel economy of 45.71 mpg at 60 mph.

I know all of these numbers are very rough, but a Cd of 0.23 is a lot less intimidating than 0.11, heh heh.

I've also taken the air conditioner belt off, and will, when next I need tires, be switching from 185cm-wide 44psi-max tires to 175cm-wide 51psi-max tires.

I'm likely going to pick up some airtabs and see how that helps the airflow down and over the rear window and trunk.

I've also pondered just riveting a flat sheet-metal spoiler onto the back of the trunk, to help airflow separation.

That Merkur looks interesting, I think if I was going to try that route I might just opt for a full Kammback instead. Which I might do, but that would be a daunting task for me at this point.

Istas,I didn't use the calculator,just ran numbers for aero.Cd 0.23 is realistic goal as I hit this with the CRX.I hope you've seen basjoos AeroCivic,he's at Cd0.17(wickedly delicious!).I did a thousand dollars in wheels and LLR Michelins and saw absolutely no improvement in MPG.I also did the AC belt delete with no reward.The airtabs might help you,as they were developed for cars like yours.I don't have any first hand experience with them.The flat sheet extending back would have to help.The Kammback with all compound surfaces are the most complicated to form,so I thought the multi-wing spoiler might be more doable.I don't understand the mention of engine efficiency at 0.21,can you help out there?------ Of course the stickys are a good source for all the mods we know can contribute to better mpg,so indulge yourself there if you haven't already.The Legacy is a great car.I've got a lot of time in a wagon model and I think it will be a great project for you.If you can get to 45-mpg it would be a real coup!Keep us posted.