Boattail the most aerodynamic car... an Insight

[basslover911]

Im finding ways to maximize a Honda insights aerodynamics before I go out and purchase one.

So far,
- Remove side mirrors
- Grille block
- Remove rear windshield wiper
- Moon discs in wheels
- Maybe extend the side skirts down lower?

And.... well thats it theres not much more! Except, a boattail!. What do you guys think? Would it be worth some extra mpg's or is the insight's shape already near perfect? Maybe a kammback?

[Christ]

I'm thinking you'd get more from designing front wheel skirts, because the rear of the car is already pretty slight when it comes to cars.

Not sure what the belly looks like, but there's almost always room for improvements.

I'm also not sure what blocking your grill will do for you car... but while we're on the subject, there's a big hole in the nose that you should probably cover up. :P

[Daox]

The underside of the Insight is fairly clean, but some touch up wouldn't hurt.

[basslover911]

Originally Posted by Christ

I'm also not sure what blocking your grill will do for you car... but while we're on the subject, there's a big hole in the nose that you should probably cover up. :P

Haha yeah that one, the top "hole" thing.

[basjoos]

Relative to the frontal area, there is still a large area of low pressure recirculating air forming behind the car that is slowing it down.

My 92 civic hatch had a shape fairly similar to the Insight's and the boattail was the single biggest mileage improver (+4mpg) of all the mods that I installed on the car. It also doubled the amount of luggage space behind the back seat and gives me 3 additional feet of crumple zone behind my car (which already has proved its worth, saving my car from being totalled and likely saving my life when I was rear ended by a high speed sports car at 4 in the morning).

A second big area of improvement is rounding the nose to lower the stagnation point. That extended nose also provides a place to install an adjustible radiator air inlet door and adds a foot of additional crumple zone as well as scooping deer over the top of the car when you encounter them.

[Christ]

Originally Posted by basslover911

Haha yeah that one, the top "hole" thing.

Spelling corrections... LOL

Grill - for cooking.

Grille - front air inlet on your car.

Just me being a Grammar Nazi (Spelling Nazi?)

[basslover911]

Well... maybe its for both!

Hmm, I wonder how a boattailed insight and elongated front would look like (if only I was good with photoshop )

Basjos, you upped your gas mileage from 39mpg to 70mpg avg. Do you think an insight would be something like from the stock 47mpg avg to 80mpg? (based on epa avg and your real world avg)?

Of course, you can add the MIMA system and other goodies, but I am just talking about aero here.

[aerohead]

At Cd 0.25,the Insight's drag can still be cut in half for another 25% better mpg ( you could expect 90 mpg hwy on a regular basis).Getting there is going to be radical and its mostly going to happen at the rear.Follow basjoos lead on that.

[basslover911]

While doing a boattail and adding a lot of space, why not move the radiator back there and completely seal off the front?

[basjoos]

The main advantages of really dropping that Cd down low is that it allows you to still get good mileage while driving at normal highway speeds and also acts as though you have more horsepower under the hood when accellerating at speeds over 70mph.