Good, yet inexpensive upgrades for wheels and/or tires. Used for commuting.

[EastPhilly]

Hello,
I am interested in upgrading the wheels and/or tires for my 2. Right now I have the 2011 OEM wheels and tires (yokohama tires). What would be a good upgrade for my general commutes? I mainly just have highway driving with about 1-2 miles of city driving per day. I don't need anything crazy for performance, but I'd like to help my mpg a bit. Right now I'm at about 33mpg average. Will lighter, taller wheels (16") and better tires make a significant increase (even if only 2mpg and more comfort while driving)? Or will it not really matter much?

 

[Racebrewer]

Step one is to make sure that whatever wheels AND tires you get are not heavier than the originals.

This isn't easy as many aftermarket wheels are heavy. Some Kosei's and Enkei's are significantly lighter and fairly reasonably priced (that's relative, of course).

The taller (bigger diameter) wheels usually go up in weight. They will have more inertia and thus be slightly harder to accelerate or slow.

Tire Rack publishes dimensions and weights of their wheels and tires for a little "light" reading.

It will be difficult to get your money back in wheels and tires in terms of better gas mileage. Intake and exhaust (if gently driven) might help more. Reflashing the ECU is also possible. You might also want to try upping tire pressure to the suggested maximum (better on gas---worse on ride).

Spend some time on Ecomodder.com for suggestions.

John

 

[molex7]

what racebrewer said is all really accurate information, especially about not making your money back.

That being said, let's get down to business you'll need tires eventually, and if you want fuel economy look for low rolling resistance tires.

Tires:
Once my OEM tires wear out i am going to replace them with:

http://www.tirerack.com/tires/tires...55VR5ASC&vehicleSearch=false&fromCompare1=yes

These ascends are low rolling resistance tires, same exact size as OEM, are cheaper than the OEM tires, and have a treadwear rating of 740, which means it should last more than twice as long as the OEM tires with 330 treadwear rating.
But of course it can't be all amazing, the ascends weigh 19 pounds each, and the OEMs only weigh 16 pounds, You'll either have to accept the gain of unsprung weight, or move to a lighter rim.

Rims:
The stock steelies weigh 16 pounds each(touring alloys weigh a little more than the steelies), and are 15x6. While not required, you could upgrade to some new rims, but try to get 15x6(not a big market), or 15x6.5, if you plan on using the above listed tires, or any OEM size tire. Avoid 15x7 and up because there are limited options when it comes to low rolling resistance tires, and prices only go up as tires/rims get bigger.

some examples of what i would be looking at:

http://www.good-win-racing.com/Mazda-Performance-Part/21-1045M2.html
15x6.5, 11.4 pounds, $94/rim

http://www.good-win-racing.com/Mazda-Performance-Part/60-1351M2.html
15x6.5, 12.4 pounds, $94/rim


If it were me, i would get those listed tires, and then the Konig Heliums(but hopefully in black). Lets do some math.

$94/rim x 4 = $376
$98/tire x 4 = $392
shipping ~ $100
mount/balance ~ $80

total: $948, the number may seem high, but for an economical fuel economy upgrade, that is easily acquired, i don't think there would be a better set readily available, for this cheap.

You don't have to go with this exact setup, but hopefully this gives you an idea of what to look for while you shop, good luck!

 

[Racebrewer]

Thanks Molex,

I have 16" Konigs on my wife's Honda Fit (Discount Tire). Really happy with them. Kosei's and sticky Dunlops on the M2.

Tire Rack will mount and balance tires and rims for free if you buy as a package. Probably Discount Tire will also.

Somewhere I heard that Tire Rack was pushing TPMS sensors, but they didn't when I got my wheels and tires for the M2.

John

 

[deadlydave]

I'm not a fuel economy guru by any stretch, but I think we may be missing a part of the equation here. The OP states that he does more highway driving than city. Would the gains he makes up around town cancel out the added energy it takes to keep lighter wheels at a constant speed?

I realize this might sound counter-intuitive, but hear me out. A friend and I have very mechanically similar WRXs. When he added rotating driveline mass by going from a light weight flywheel to a stock flywheel, his highway fuel economy jumped from 21-22mpg to 26mpg.

Another thing to consider with low rolling-resistance tires is the braking and cornering limits will be lower--and ABS, traction control, and stability control, at least in theory, could all be affected. I'm not trying to fear-monger, just add some other considerations.

You could also try running 14" wheels/tires. Discounttiredirect does have steel wheels in that size that they say will fit.

 

[molex7]

From my reading, which is mostly from ecomodder.com, the general consensus is that lightweight wheel will have a greater effect in the city, because you constantly stop movement, and then have to get the unsprung weight moving again. That being said, it's still a gain on the highway, the weight of the wheel is constantly being shifted up and down as the wheel rotates, so if you have less mass rotating, it will rotate easier. Also our stock yokohama avids are actually really light, weighing only 16 pounds, most tires seem to weight around 18lbs+ each, so almost any tire change is going to yield extra weight.

From what you describe it sounds like you are arguing for kinetic energy, like when you have a really heavy shopping cart and push it and let it go, it will travel farther then an empty shopping cart. The problem is it takes a lot more power to get that cart moving, in a supermarket setting you wont really think about long term as you only push that cart for a few minutes, in a small automobile with a power::weight ratio of 23pounds/horse-power this would be very draining and you would see negative effects to run a bigger/heavier wheel. Again this effect would be much harsher in the city where you are stopping/starting, but even on the highway it will make a difference, because that weight is constantly moving up and down as the wheel rotates.

As for low rolling resistance tire performance they aren't really "bad", low rolling resistance doesn't necessarily mean low grip/performance. Especially now that more tire manufacturer's are producing LRR tires, it's a much more competitive market, and most consumers are not going to settle on a crappy tire(when they are buying a complete set). But you aren't wrong, they are definitely not going to compare to other tires, they are meant to be driven easily, not in a performance environment.

Small diameter wheels will make a pretty good difference. The same basic principals apply, small wheel = less weight, easier to start/accelerate, less weight being rotated. However there is always a trade off, there are less 14" tires readily available as 15"+ has been the industry norm for 10+ years. There are some very nice 14" rims though, like the Civic HX rims, which i believe weigh 11 pounds each, and even smaller than that would be the civic VX 13" rims, which iirc weigh 8.9 pounds each. Both of those rims came from honda's most efficient vehicles in their respective times ~92-99.

 

[utmorpheus]

Also keep in mind that lighter wheels are much easier to damage on potholes and other road conditions. Going to a lower profile tire(due to larger rim diameter) is going to make the chance of this happening even greater. Being a DD I would seriously consider sticking with stock wheels and getting a good tire, or buying a 15" Miata rim from a 99-02 car. They are 13.1lb each, have the same lug pattern, same hub size, and are the same 15x6 of the factory 2 rim, and you can usually find an entire set for <$200 if you're not worried about perfect aesthetics. I'm running them right now on my 2 with some Dunlop Direzza Z1 tires and the car feels COMPLETELY different. It feels planted in straight line and cornering in a way that the Stock Yokos couldn't dream of.

 

[deadlydave]

*informative, thought-provoking post*

As for the low-rolling resistance tires, I agree that they are continually getting better. The prius optional 17" LRR tires are the standard equipment on the Subyota coupe.

I was arguing for inertia due to rotating mass. Though, On a lower-power car like our beloved 2's, there seems to be a high probability that the mass would be more of a detriment than a benefit. (uhm)

 

[Setheronie]

Also keep in mind that lighter wheels are much easier to damage on potholes and other road conditions. Going to a lower profile tire(due to larger rim diameter) is going to make the chance of this happening even greater. Being a DD I would seriously consider sticking with stock wheels and getting a good tire, or buying a 15" Miata rim from a 99-02 car. They are 13.1lb each, have the same lug pattern, same hub size, and are the same 15x6 of the factory 2 rim, and you can usually find an entire set for <$200 if you're not worried about perfect aesthetics. I'm running them right now on my 2 with some Dunlop Direzza Z1 tires and the car feels COMPLETELY different. It feels planted in straight line and cornering in a way that the Stock Yokos couldn't dream of.

Awesome, I swear I'm about to get some used miata wheels now. xD