Hood aero optimizations

[TheBrian]

My old commute was 65mi/week, at a typical speed of 40mph. My new commute is 175mi/week, with 90% of that distance at 70mph. Naturally, this has me thinking about aerodynamics.

 

I know Subaru designed the BK Legacy competently, and its coefficient of drag is very respectable for a mid-90's station wagon. I know, no matter what I do, I'll never get so much as +1mpg at 70mph. Still, I feel like tinkering.

 

So, I could tape up the gaps between bumper cover and body. I've already removed the roof rack crossmembers.

 

I notice the Prius has a spoiler. That wouldn't be there if it didn't reduce drag. I notice interesting trailing edge aero devices on the Outback wagon, the new BMWs, and some Mitsu Evos. Thus, I'm left wondering: how could a trailing edge spoiler reduce drag, and why doesn't the Brighton have one?

 

Air enters the engine compartment through the grille and other gaps. It all has to exit below and behind the engine. I'd like some vents. Okay, I'd still want hood vents even if they had no aerodynamic purpose. They look cool.

 

How about I install a hood scoop off an Outback upside down on a Brighton? More trouble than it's worth, absolutely. But would it reduce drag?

[NoahDL88]

what milage are you getting?

 

 

The easiest and cheapest way to increase your mileage, slow down, i always ran late on the way into work, but on the way home i'd take it nice and easy, i think i averaged 26 in the 91 legacy sedan.

 

also, get rid of all the mc donalds junk in the back of your car, you'd be supprized what a little weight savings will do for your MPGs

[TheBrian]

My mileage is great: ~27mpg. Weight savings: Done that. But actually, weight savings won't help me save much gas since I seldom brake anyway. In the case of a 70mph freeway cruise, I'm only spending power on: engine inefficiency, driveline losses, aerodynamic drag, and accessories.