Prius C: thinking of developing a "70 mpg aerodynamics kit"...
 

I am excited to be picking up my Habenero Prius c tomorrow and have been doing some thinking...

I build custom trikes and have access to a pretty good fiberglass guy and what not so just how hard (possible?) would it be to do a "package" possibly including disc style hubcaps, grill block, lower front air dam, and either a kammback or possibly even "storage enhancing boat tail"

Think 70 mpg with the air on at 65mph is a reasonable goal for the masses to achieve?
Tom

Go for it! Yours is the show car. Gauge responses. The fiberglass, though heavier, will have the quality paint finish matching quality that the masses MIGHT go for!

I look forward to hearing more about this from you in the future!

good luck!

http://www.mooncraft.jp/yuratakuya/g...prius03-04.jpg

http://www.autofiends.com/wp-content.../mooncraft.jpg

http://www.mooncraft.jp/yuratakuya/g...prius02-01.jpg

It would be cool to see someone really market them :)

I would like to say I love the idea, but I think 70 mpg is going to be a very hard goal to hit.

I generally get 55 mpg @ 60 mph with my Prius in summer. If I plug in all my data (2900 lbs, .01 Crr .26 Cd, 22.4 sq/ft) into the aero & RR calculator and tweak my engine efficiency to .283, I can get the calculator to spit out 55 mpg @ 60 mph. Now, if we substitute the Prius c numbers in with 2500 lbs, the stock Cd of .29, and 22.1 sq/ft of frontal area (keeping the .283 engine efficiency and .01 Crr) we get just above 54 mpg @ 60 mph. If we bump that up to 65 mph we've now dropped down to just over 48 mpg. So, 48 mpg is roughly where you'll start. In order to get the 45% increase in mileage to get 70 mpg, you'll need to reduce the Cd down to roughly .167! That would require a TON of work to achieve. I'm not saying its not doable, but it is going to be a lot of work.

Rear wheels skirts should be part of the kit, too I think. And the Kamm back needs to have wheel strakes as part of it, like the Mooncraft.

The tail will be a must as part of the kit if you want to try to approach 70 mpg.

One of the problems you will encounter is when you reduce the overall load, you also reduce the engines efficiency. Without lower engine RPM at the higher speeds you will not be able to maintain the load that is essential for high BSFC.

regards
Mech

Old Mechanic - fortunately in this case, the car has a CVT type of transmission. So it should automatically compensate for the reduced load by reducing RPM.

Aeromodding a CVT equipped vehicle is a 2-birds-1-stone type of deal.

That isn't nearly as much of a problem on the Prius' enigne as it is on most other engines. Almost anything off idle rpm is pretty near max BSFC.

http://ecomodder.com/wiki/images/d/d...prius_bsfc.jpg