15" Tires on a model five.

Me too!

Many folks insist they are not losing any mpg with the 17" wheels on their model 5 or Plus Package and I believe it is hogwash. No one that I know of has done the swap using LRR summer or all-season tires. The only swaps I have observed were using 17" wheels in fair weather and 15" snow tires in the winter. That is not a valid comparison IMO.

 

In a Prius meeting here in Pt, a mate with 15" got less 0,1-0,2 l/100 on the same route as mine with 17", and I was following him with no useless braking...

 

Again, this is not apples to apples since we are talking about 2 different vehicles...

Swap wheels then run the same commute in the same weather with the same driving techniques or the course of a week or two. This is at minimum what would be required to determine the difference.

 

Also intersted in MPG vs wheels. I will have the OEM 15's that are on my 2010 prius 4. I am interested in the best mix/mpg and asthetics...

Will OEM's give best MPG?

Are smaller wheels better?

What OEM options are there?

Thanks-

 

I keep thinking that 16" wheels with 205/55R16 tires is the best balance between looks & mpg.

 

Totally agree!

 

Thanks MR2. In theory I agree with what your saying simply becuase its a little of both. But, is there an OEM option at 16"?

Are there any "Fuel friendly" prius wheels out there yet?

 

It's not so much the wheels that get you but the tires. Get the lightest and narrowest wheel you can afford but pay special attention to the tires! You want a narrow, LRR tire that is light and fits your needs best.

 

Many? It's only a few members and we quickly call them on it. Most of us believe the ~1.7-1.8 mpg hit that the published European version of EPA testing indicates. Given this minor hit, any actual trials done by members here would be subject to bias, as it'd be difficult not to subconsciously drive more effectively when swapping wheels. One can easily bring it to over 50 mpg actual using hypermiling techniques (I've done it).

 

I asked a guy that I work with that has a Prius 5 & he said he gets about 47 mpg on the dash readout. So that sounds like 44-45 calculated but he never keeps track like most drivers.

 

These numbers were taken from the Bridgestone Ectopia E422 off of Tirerack.com website spec sheet.

195/65R15 = Dia. 25.0" Width 7.9"

205/55R16 = Dia. 24.9" Width 8.4"

215/45R17 = Dia. 24.7" Width 8.4"

205/50R17 = Dia. 25.1" Width 8.4"

 

That would be near impossible to find since that would be a 185 width tire & would be too small in a 185/65R15 size. Maybe a 185/70R15 but that is a little taller at 25.2". A 185/60R16 would also work but I don't know if anyone makes one in that size.

 

Toyota EU estimates have different values for 215-17 and 195-15. The difference is about the same: about 0,1 l/100 + when fitted with 17".

I would like to try that, anyway.

 

It appears I may pick up a 2012 Model Three this weekend. If so I'll get to test the 15s vs. 17s mpg difference this summer.

 

Shotgun!

LOL congrats F8L!

 

It's interesting that the Prius Plug-In doesn't use 17" wheels, even when in the loaded $40K Advanced Trim, with just about every other option but the weight adding moonroof. This suggests some rolling resistance and fuel efficiency hit, unfortunately not how much.

Personally, I prefer to use a smaller rim with tires inflated to a higher pressure. It doesn't give the larger contact patch, greater traction and higher rolling resistance, but it does offer a similar turn in response and ride.

But then I believe most of the market has moved to larger rims and very low profile tires primarily for cosmetic, not engineering reasons.

 

Toyota reports a coefficient of drag of 0.25 for the Prius.

However, a study conducted by General Motors disputes this claim for Prius V models and found the value for the model with 17" wheels to be around 0.30 based on tests in GM, Ford, and Chrysler wind tunnels. Therefore, at least according to this study, the 17" wheels on the Prius V do create more drag and thus potentially reduce mpg.