3rd gen Prius aeromod thread

[bike4miles]

The trend i see in the front wheel difuser pics is the the difuser is positioned for the supension rather than the tire. This is a big gaping hole in the underside of the car which cant be covered with a flat static pan so a difuser is the next best thing. Very nice collection of pictures there!

I love this thread by the way. I just got a 2013 prius I'm looking to do some mods to. Nothing as extreme but im thinking rear wiper delete, antanna change, and a mod to the factory wheel covers. Its cool to see why the car would look like with more extreme mods!

[California98Civic]

Originally Posted by Vman455

.... Hucho has some suggestions for mitigating that gap in Chapter 5; radiused corners and a fin down the center gives almost the same drag reduction as a full gap-filling treatment on a trailer. Since this will probably behave better than a trailer, being closer to the body than any trailer could be, I'll go that route and see what it does.

That fin could be collapsible so as to allow access to the hatch for loading.

[redpoint5]

Are the MPG results in yet?

[Vman455]

Pulling this thread back up from the dead to put these pictures in one place. I took them today at an abandoned gas station, of the Prius as it sits now. Just finished installing the converter cover this morning (mainly to prevent catalytic converter theft, but there should be some drag reduction from closing off more of the underside than the stock shield).

Based on the Audi A2 Tata/Warwick test of aerodynamic add-ons to a production car, I estimate it's sitting at ~0.20-0.21. I intend to calculate a more exact number in the coming weeks from a coast down test with wind velocity and temperature correction (I bought a Kestrel NV250 to provide that data).

Cue the picture dump.

Intake blanking


Blanking plate is now behind the grill, made of diamond aluminum sheet. Upper grill is open. Total grill area open to airflow is exactly 1/6 radiator area.

Wheel housing fairings (2018 Ford C-Max Hybrid)




Cribbed from Ford. Both are attached with plastic push pins; I added some plastic sheet in front to attach to as well (the Gorilla tape is just to seal up the exposed edge gaps).

Enlarged front wheel strakes


I've taken to calling these "strakes" as Honda marketing does. Made of indoor/outdoor rubber mat, these have held up for 2+ years now.

Hood opening gaskets


The hood opening is gasketed all the way around now--as in the current Prius Prime (but not regular Prius, oddly enough)--rather than just the front and back.

Front and rear air curtain ducts




Made of thin aluminum sheet. Convergent ducts emit sheets of faster-moving air over the wheel openings. I modeled the inlet/outlet sizes, placement, and direction/angle off the Hyundai Ioniq (front) and Honda Clarity (rear).

Exterior mirrors


Removed and holes plugged with fiberglass.

Extended catalytic converter cover


Courtesy of Miller in California. The other exhaust shop selling theft-prevention covers has a design that must be riveted in, so I went with this one that bolts in (using three different bolt heads) to rivnut inserts. Drilling through multiple steel sheets in the car's underbody was a b****, but otherwise it's an easy installation. Hopefully this makes the Prius a less-attractive target than the car sitting next to it, if it ever comes to that.

Smooth roof


The rear washer nozzle and antenna have been removed (along with the complete sound system).

Reduced ride height


Body has been lowered ~35mm with Tein H-tech springs, as detailed earlier in this thread (I think I installed these at 4,500 miles).

Rear air splitters (2012 Honda Insight)


Fairings from an Insight that sit behind the rear wheels and curve inward.

Rear window wiper


Removed entirely and plugged with a nylon cover.

I'm ready for my closeup, Mr. DeMille

[freebeard]

Can you suggest a search term? 'toyota passive plasma strips' doesn't cut it.

Or are those for conspicuity?

[Vman455]

There have been a few threads; search "conductive tape" or "Toyota patent." Here's the patent on Google.

[19bonestock88]

Such a simplistic air curtain works? Doesn’t the outlet need angled outward a bit?

Would the conductive tape work with an all plastic body?

[pugmanic]

Where has the amazing tail gone?

Love all the other aero mods.

[Vman455]

Originally Posted by 19bonestock88

Such a simplistic air curtain works? Doesn’t the outlet need angled outward a bit?

Would the conductive tape work with an all plastic body?

The discharging tape works specifically on plastic/resin panels--metal ones don't need it, according to the patent, since they're conductive themselves.

It's hard to see in pictures, but the front curtains follow the angle of the bumper cover and thus are angled outward (the rears are straight back). If I had retrofitted internal ducts from an Ioniq as I originally considered, the outlet would have been at the same angle (since the bumper cover forms one side of the duct in either case), but moved inward 15mm. We'll see; the nice thing about this design is I can remove them with just a few screws on each side, so testing their actual effectiveness isn't out of the question.

[Vman455]

Originally Posted by pugmanic

Where has the amazing tail gone?

Love all the other aero mods.

Similar to Hucho's first project at VW, I want to see how much I can lower the drag coefficient while keeping within the footprint of a conventional sedan. (He was able to match the "pumpkinseed" car with a truncated form the same length as a Passat).