Prius Prime Rims

Same wheel specs, as far as I can tell, as on any of the GenIV cars. Lots and lots of wheels threads in those sub forums. Just do a search or poke around in there for a while. Lots to read and full of pictures.

 

I would check if the OD of the tires are the same. Otherwise, I wouldn't even begin to consider it.

 

Short answer: None.

Longer answer: Forged wheels are lighter than cast wheels so a 17" forged wheel could be lighter than the 15" cat wheel Toyota chose. Sadly, you will find that forged wheels are 3 times the cost of cast wheels and that light ones are even higher cost.

Wheel Tech Information - Wheel Construction

To hold up the same weight, a low profile tire needs to be wider than a higher profile tire. So you will find the 17s are all wider than the 15s they replace. And width will mean higher air resistance, to some minor degree.

It is also harder to make a Low Rolling Resistance tire in low profiles, so on the average the best 15" tires are lower in resistance than 17"s.

Sorry.

(The 'normal' Prius accelerates harder, brakes faster, and handles better on 15"s than on 17"s, according to Car and Driver)

 

Is the Prime's stock rim solid alloy, no plastic? Or no?

Looks like no, from Toyota.com:

15-in. 5-spoke alloy wheels with two-tone wheel covers and P195/65R15 tires

Joy joy, I guess.

 

I'm curious how much of the MPG loss can be mitigated by using a forged or lightweight wheel in plus sizing. These wheels are nice looking and light: BBS RF Forged

 

That's an expensive rim, wow. How much does it weigh? Couldn't find.

You might be over-stressing the mpg penalty. Our 2010 Canadian Touring has the OEM Toyota 17" rims: they are porkers. Our lifetime average is 4.9 liters/100km (48 mpg US). The tires are still the OEM's: Michelin Pilot HX mxm4, but they may be special OEM edition, they have the GreenX label, Michelin's LRR logo.

Our driving is an eclectic mix, both my wife and I driving, fair number of short trips. We care, do try to drive economically, but we're not rabid hypermilers.

I've always liked the look of the third gen style Prius Plug-In rims, 15" rims, fwiw.

 

On the 2016 Prius, the tire sizes are 195/65R15 and 215/45ZR17. When mounted on the stock wheels, the OD of the 15" tire is 1 cm larger. There will be a .9 kph speedometer error. I used a Web based wheel calculator. I don't know how the Prius computer uses the wheelsize, but it could screw up how the car performs, its economy, etc. in addition to the speedometer error and mileage calculations.

 

The diff in revolutions (per mile or whatever) is 1.4%. Fairly trivial. The speedo is always off tending to read slightly higher than reality, due to legislation. Basically to encourage people to slow down a bit. The odometer should be reasonable accurate. I would think Toyota would try to avoid the odometer reading high, that can lead to lawsuits, such as Honda had a decade or two back: cars were running out of warranty sooner than they should.

 

The Plus X calculators on tire sites keep the OD the same, or close enough that it is only an issue for the anal attentive.

In short, not enough for the cost.

If the same weight as the smaller wheel, the weight of those wheels will be moved further out from the axle. It might be slight, but that has a negative effective. Jimbo pointed out that the tires will be wider. Along with more air resistance, this could also mean a larger contact patch that will raise rolling resistance.

Some markets require fuel economy ratings for different sized wheels to be published if available. The Prius numbers can give an idea of how much impact 17" wheels will have on the Prime. Only found CO2 emissions on the Toyota UK site; 70g/km to 76g/km.

Roughly works out to dropping 54mpg to 49.7mpg. Still great for a car, but the wheels will also effect EV range; that drops to about 22.8 miles.

 

It's 14.3 lbs in the 17" size. Pretty lightweight and strong due to the forged construction. These cast wheels (click) are 30lbs in comparison. I chose the lightest vs heaviest wheels to compare.

 

How does that compare to the Prius/Prime 15" wheel weights?

 

Approximately 15 lbs. This gentleman did some significant tests: '16 OEM wheel weights & options | PriusChat

 

Posted via the PriusChat mobile app.

 

The contact patch for the same load and same inflation pressure will be about the same regardless of tire width. A wide tire will have a wider, shorter contact patch. A narrow tire will have a longer, narrower contact patch. It might be said that the rolling resistance might be less with the wider tire. A narrow tire has a longer patch that has to deform to flatten and contact the road surface. The wider tire has less deformation for contact.

With snow tires, Continental has an article that says that the wide tire has more sipe edges grabbing the snow for better traction.
Wide tires

The stock Prime wheel is a spoked alloy wheel that would look OK on its own. It is covered by the aerodynamically smooth wheel cover.

Interesting to see the Prime photo above. The roof bars will hurt gas mileage. If you need them, use them. Otherwise, take them off. I see people with all types of cars running with the roof bars and accessories...bike racks, kayak racks, big square cargo baskets, all year long. Dumb.

 

Hey I like your Prime in your picture, I see that either you (or the dealer) ordered the optional 10 spoke 15" rims. I wish I had done that when I was waiting for mine to get made and float across the pacific. I was so obsessed about every other accessory (I got them all except for those wheels and the Security System which I was told was not available even thought it was in the brochure). Now I wished I got the wheels. But I did some more research and the 4 Touring Prius comes standard with 17" rims. So since I am contemplating purchasing new rims, why don't I do like you are and get the 17" ones? My concern is that the speedometer might be off due to the different size? Would there be some kind of recalibration in the computer? Would Toyota not support this? Has anyone else upgraded their Prime rimes?

If you do upgrade yours, maybe I can buy your used 15" rims since you won't need them? Can I get a Toyota part number for these?

 

Wondering how the 2012 PIP rims would look, on the Prime:

Prime with stock rims:



With PIP rims:

 

Looks fantastic! Congrats.

 

I have a 2010 Prius and I am looking to put after market rims on. The size really doesn't matter to me. Should I look at 15's for best gas mileage? Also where is a great place to get a good deal online?