Three 2017's on my dealers' lot, including a GT

[wellswebdesign]

I just got back from my having my 2 recalls done, and saw the salesman that originally sold me my car. We talked a bit, asked me how I liked the car, etc. I asked about the 2017s, and he showed me the 3 they have so far. They're in the back until they can clear out the 2015s.

I took a picture of the GT tires, wasn't sure if anyone had info on those yet. I know some people are big on tires, I'm not picky so am with the stock.

Also saw a drum of the 0w20 oil they used. Yahoo.

The salesman told me there's a customer at the dealer that had the passengers seat removed because they do a lot of deliveries. A *LOT* of deliveries. He said (this was a salesman, now... no offense to any salesman out there) they had 152,000 miles on the car, with not a single problem. I like my salesman, he seemed honest. When I bought it, he told me that the manual gets better MPG than the CVT, despite what the EPA sticker says. That, as you all know, ended up being true. He also said that he was hoping the 2017s would have better sound insulation, but they don't. So, he seems pretty honest to me.

As I walked in through the garage from the back, I saw them re-flashing my ECM. The guy was kneeling by my drivers seat with what looked like a thick tablet with a color screen.

That's on big stream-of-consciousness post, sorry.

[Top_Fuel]

I took a picture of the GT tires, wasn't sure if anyone had info on those yet...

Awesome! Thanks!!!

I have been wondering about these tires. This size tire (175-55-15) is virtually identical in diameter to the 165-65-14 base Enasave tires. So it might be helpful for anyone wanting to go with 15" wheels while retaining an accurate speedometer and low rolling resistance.

This Yokohama is the only 175-55-15 all-season low rolling resistance tire used in the US. My local Discount Tire says they don't exist in their system, and Tire Rack doesn't show them yet, either.

[ComputerAbuser]

Would there be any fuel economy benefit going with a 175-55-15 instead of a 165-65-14?

[25Plus]

Would there be any fuel economy benefit going with a 175-55-15 instead of a 165-65-14?

No, fuel consumption would be slightly higher because of worse aerodynamics and higher weight of the tires and rims.

[ComputerAbuser]

No, fuel consumption would be slightly higher because of worse aerodynamics and higher weight of the tires and rims.

Ya, after posting the question, I looked into it some more and came to the same conclusion. That's too bad; I would prefer the look of 15" tires, but not at the expense of MPG.

[ed100]

The GT is cool, but I like my 5 spd.

[Top_Fuel]

That's too bad; I would prefer the look of 15" tires, but not at the expense of MPG.

I'm definitely moving up to 15" wheels...and I think I can do it while minimizing the fuel economy impact.

The factory 14" aluminum wheels weigh about 13 lbs...and a 165-65-14 tire also weighs about 13 lbs (26lbs total). Note: I bet a 2017 15" Mirage GT wheel/tire weighs at least 30lbs. Those wheels do not look light!

I just bought a set of aftermarket 15" wheels (Konig Helium) that weigh 11 lbs each (2 lbs LESS than the OEM 14" wheels).

I'm still considering tires. A 175-55-15 weighs 15lbs (which would put me at 26lbs total for a 15" wheel and tire). The overall weight is the same as the 14" wheel/tire combination. As long as the 15" tires are low rolling resistance, I think the impact may be small.

The only problem is that there is no 175-55-15 all-season, low rolling resistance tire available in the country right now. They might be putting these Yokohamas on the 2017 Mirage GT, but I can't find anyone who stocks them! So don't buy a GT and get a flat tire!

I'm considering 185-55-15 Bridgestone Ecopia EP422 Plus tires. Yeah...these are slightly wider than 165's, but these Bridgestones are almost always at the top of low rolling resistance ratings...and they have a longer treadlife than the Dunlops. So it's possible that any small mpg loss may be (financially) offset by the fact that you won't be replacing tires every 35K miles. I have the previous generation Ecopias on my G5 and they deliver good mpg's and will have no problem reaching 70K miles.

I'm still in the middle of all of this. I'll post a detailed update once I pull the trigger and get tires for these wheels.

The guys who don't care about fuel economy buy 17lb wheels and then put heavier/wider 195-50-15 tires on them that don't have low rolling resistance.

[Donut]

The lighter wheel could be favorable if it were only made from a solid piece of metal, i.e., just comparing weight and radius gives you a smaller moment of inertia by a factor of only 0.97, i.e., almost no advantage (11*15^2/13*14^2). However, the weight distribution is what matters more and could in fact mean that your lighter but bigger tire still has a higher moment of inertia, depending on where most of its material is located. The more of the metal is farther away from the rotating axis, the larger the moment of inertia will be. The moment of inertia grows only linearly with mass, but increases with the square of the distance from the rotating axis.

All of this, obviously just a comment disregarding other effects such as rolling resistance and friction in the axes, and so forth.

[cyclopathic]

No, fuel consumption would be slightly higher because of worse aerodynamics and higher weight of the tires and rims.

It would be lower but for different reasons.

Lower profile tires have higher rolling resistance due to higher sidewall losses. Weight difference is negligible, and aerodrag alone will not explain loss at lower speeds.