Simple aeromods?

[KarenRei]

I just got my first Insight. I'm an efficiency nut (I had been waiting for an Aptera, but that went nowhere ). I'm not super-mechanically-inclined, but I can hold my own. Are there any relatively simple aeromods out there that people here have done and tested their results? I already have the air intake partly blocked for winter (the previous owner actually was already doing that)

What always comes to me first is the concept of a plexiglass cowling over the rear to continue the rear windshield's taper (along with the side and underside taper. I don't think I'd have any trouble building it, although I'd need to find a way to attach it to the vehicle, preferably in a removable manner. I'd also need to make sure that it doesn't induce extra vortices or cause lift or downforce which could be counterproductive, but I could probably check on airflow by injecting steam or smoke upstream, or by the old-fashioned "tape ribbons to the body and see how they flap around" approach. My big concerns, though, are that the police wouldn't be happy -- if not for it covering the lights and plates (albeit transparently), for the fact that it'd also cover the rear bumper. :P

Several other things also stand out as problem areas, although not as significant. Thinner side mirrors would help. The front and rear windshield wipers are certainly disrupting the laminar flow, although I'm not sure how to properly shroud them when not in use. The front of the car is a good ways off from the ideal oblate hemispheroid aerodynamics calls for, but there's nothing that can really be done about that. And shrouding the front tires seems like it would be very difficult indeed.

Anyway, what have other people around here done to improve their vehicle's efficiency?

[chris22104]

Join ecomodder.com and look at 3-wheeler's posts showing detailed aero mods (tons of step by step pics.) These include under body and boat tail. The best and most extreme gen 1 insight mods you'll find.

[KarenRei]

Thanks!

[RobertSmalls]

For simple aeromods, you can't beat a grille block. Mine's foam and fiberglass, and documented at EcoModder.com. You could probably make one out of plexiglas if you wanted to.

Deleting the rear wiper was an easy decision for me. I only turn it on when going <20mph in a harsh snow storm. At any higher speed, snow blows right off. I now have a $0.95 plug in place of my rear wiper motor & arm.

Front wipers probably don't protrude into the airstream. See GasolineFumes' and Basjoos' testing at EcoModder.com. The aerodynamic penalty is not zero, but not large.

Passenger mirror: I got rid of mine. I have a 17" convex rear view mirror that does the job better than the stock arrangement. I'd like to get a 4", convex, interior mirror for the passenger side this summer as well. Convex is key here.

Driver's mirrror: If I find a really good solution for the passenger side, I'll copy it to the driver's side, and add a bicycle mirror to satisfy my state inspector.

Wheels: They rotate! Keeping the tops of the wheels out of the airstream would be a big help. Front wheel skirts would be ideal. Spandex? Hinges? For now, I have flat fiberglass front hub caps, which are second best.

Congratulations on your Insight. I'm sure you'll love it. Btw, your name is familiar. Are you on SilentPCReview, or some other car forum?

[KarenRei]

Yep, already have a grille block I haven't had a chance to drive it enough yet to see how much accumulates on the rear window, but if it's as mild as you make it out to be, removing the rear wiper should be a no-brainer.

Did you ever spend any time on the Aptera forum? I used to be really active over there. Alas, poor Aptera...

[RobertSmalls]

Originally Posted by KarenRei

Yep, already have a grille block I haven't had a chance to drive it enough yet to see how much accumulates on the rear window, but if it's as mild as you make it out to be, removing the rear wiper should be a no-brainer.

I've never missed it, but try it for yourself. See how long you can go without reaching for the rear wiper controls. You will need to keep a coat of Rain-X on it, though.

Originally Posted by KarenRei

Did you ever spend any time on the Aptera forum? I used to be really active over there. Alas, poor Aptera...

Ah, that would do it. I never posted there, but I was a big fan back in the days of the first prototype. Then they fell a few years behind (the original) schedule, said they wouldn't be able to beat the major automakers' EVs to market, and I lost interest. Hence, aeromodded Insights.

Btw, did you follow Edison2's Very Light Car? Excellent stuff.

Anyway, I hope you find some mods you like over at EcoModder, and hopefully you can develop a few original mods of your own for the rest of us to get ideas from.

[JoeMultihuller]

Hi Karen, welcome to Insight Central! Really enjoyed your tech contributions to the Aptera Forum - so sad that the promise of that vehicle was squandered...

Before you even make any changes, you'll find the Insight wonderfully responsive to even the simplest of hypermiling techniques. Practice, practice, practice, and you'll soon be achieving your first 800-mile gastank. You'll find that the archives on this Forum contain years of excellent technical hints and mods.

You'll soon discover how unique this Gen1 Insight is; if you have the 5-speed you'll find the further enhancement of 'lean-burn' which provides a significant mileage improvement over the CVT.

If I may suggest, you might reset your lifetime MPG so that the readout displays YOUR mileage. Make use of the trip displays; for example, I use Trip A for gastank mileage, Trip B for trips, and FCD for intervals within a trip. My original goal for my 5-speed was to achieve a lifetime mpg (lmpg) of 75, but now, at over 70,000 miles I find myself vacillating between 77.7-80.0 lmpg.

Again, welcome to the group and enjoy your technically unique and distinctive new toy.

JoeS.

[red1dr]

Originally Posted by JoeMultihuller

Before you even make any changes, you'll find the Insight wonderfully responsive to even the simplest of hypermiling techniques. Practice, practice, practice, and you'll soon be achieving your first 800-mile gastank.

+1
I haven't bothered with aero mods because:
(1) the car has a very low Cd and frontal area already, so further aero gains are likely to be small
(2) aero drag goes as the square of the speed, so simply slowing down yields big gains.

Basic methods like driving at the speed limit or below when possible, increasing tire pressures, maintaining a good "buffer" ahead, timing lights, coasting downhills in neutral (engine off if you have MIMA) have a large effect. Reports here suggest that those who drive MT Insights "normally" (whatever that is) get around 60-ish mpg on the highway. Using these methods, Joe, me, and others are averaging around 80mpg (he's 77-80 lmpg, I'm at 84 lmpg) or more in some cases. Seems unlikely that any amount of aeromods would yield +20mpg, no?

I'm not sure to what extent the "normal" drivers see a difference in mpg between summer and winter. Driving the way I do, I see huge improvement in the summer. LMPG is 84, but summer trips often yield 110mpg or more. And of course winter trips give 80mpg or sometimes less.

It's important to keep in mind that the Insight-I's ICE is basically the size of a typical (these days) motorcycle motor, but produces far less power - probably half the peak output - for a vehicle that weighs three times more. It's designed for efficiency, not power. Driving at high speeds requires more power, which forces it outside its efficiency envelope.

Anyhow, that's how I see it. Others here focus on aeromods to enable them to drive at higher speeds in lean burn. Lean burn is certainly a Good Thing, but I'd rather be in LB at say 100mpg than at the very lower limit of LB.