18 or 17s aftermarkets on a 2012 3

[SonicBoom]

Hi Guys:

I'm looking to get after market Enkei's and performance all seasons in the spring/summer and want to do my research ahead of time.

Firstly, does installing outside of the stock 16 size mess up the sensors (speedo, odometer) etc and does it drastically reduce fuel economy?

I'm looking to EKM3s - > 18x8 +35 5x112. How does one know what sizing numbers are the best? My requirements would be to not lower the car in any way, not mess up the sensors and try to maintain fuel economy. What sizing numbers does that lead to?

Any help greatly appreciated.

[loki]

there's a set of 17's EKM3s for sale in the classfieds.

going 17s instead of 18s will save you money on tires.

[loki]

and link

http://www.torontomazda3.ca/forum/showthread.php?59499-FS-EKM3-17-x-7-on-205-50-17&p=864387&viewfull=1#post864387

[SonicBoom]

how bout the other stuff in terms of car changes and sensors?


and link

http://www.torontomazda3.ca/forum/showthread.php?59499-FS-EKM3-17-x-7-on-205-50-17&p=864387&viewfull=1#post864387

[loki]

how bout the other stuff in terms of car changes and sensors?

of course

[terapr0]

unless the 2012s are different from all other MZ3s, you'll need 5x114.3 and not 5x112 bolt pattern.
And your odometer / speedo won't be affected as long as you use a tire that maintains the outer diameter of the wheel. If you buy a nice light set of forged rims (not enkei's) you could actually see an improvement in fuel economy over the heavy stockers

[SonicBoom]

Sorry for the ultra n00bness, can you explain that part a bit more?


unless the 2012s are different from all other MZ3s, you'll need 5x114.3 and not 5x112 bolt pattern.
And your odometer / speedo won't be affected as long as you use a tire that maintains the outer diameter of the wheel. If you buy a nice light set of forged rims (not enkei's) you could actually see an improvement in fuel economy over the heavy stockers

[loki]

in the simplest way possible

your car records your speed by the rotation of the wheel. If you put on a bigger tire than stock, then with the same rotation of the wheel you're actually travelling faster, so your speedometer will read low.

If you put on a smaller tire, your speedometer will read high.

get it?

[zzz3]

Sorry for the ultra n00bness, can you explain that part a bit more?

this tool will help you visualize plus sizing and down sizing:
http://www.miata.net/garage/tirecalc.html

i went from stock 16s - 205/55/16 to 18" rx8s - 225/40/18 for the summer. my speedometer was .8% off, so when i did 60mph, i was actually travelling at 60.5mph. the difference in diameter is minute and as a result i didn't have any issues (and neither should you). furthermore, the mazdaspeed3 uses the same diameter tires 225/40/18 from the factory while the GT models use 205/45/17. any of the a fore mentioned sizes will keep you in factory spec.

as for rims, my recommendation would be to go with 18's if your budget permits (however 18" tires are more expensive than 17" tires), as the wheel wells are massive on the 2nd gen 2010+ mazda3s. 17's look rather small on 2nd gen in comparison to the 1st gen which had smaller wheel wells. looks aside, the real dilemma is that if fuel economy is of concern, you will need to find relatively lightweight wheels. 18" and even 17" EKM3's are quite heavy at 20lbs and 25lbs for the respective sizes. As a comparison, 18" RX8's are 21lbs and for even lighter wheels, enkei RPF01s are 18lbs or less depending on size/width! The stock 16" wheel and tire weighs in at around 42lbs if i recall correctly, so anything similar or less should not negatively effect fuel economy.

some universal specs to abide by
bolt pattern: 5x114
hub: 67.1mm (minimum)

EDIT: i forgot to add that 18x8 wide wheels all the way up to 18x9 will fit easily on the 2nd gen (even when lowered, be it .5" or 1"+). you could go smaller than a 8" width, like 7.5, 7 etc., but it wont look good as the tires will have a bulge where it meets the rim.

[Kiyomi]

looks or performance is what u should be asking. :D

[Felks24]

furthermore, the mazdaspeed3 uses the same diameter tires 225/40/18 from the factory while the GT models use 205/45/17. any of the a fore mentioned sizes will keep you in factory spec.

Good info, thanks. The GT uses 205/50/17 though.

[SonicBoom]

zzz3 you are the man... thanks so much for the detailed info....18s it must be.....

[shu5892001]

unless the 2012s are different from all other MZ3s, you'll need 5x114.3 and not 5x112 bolt pattern.
And your odometer / speedo won't be affected as long as you use a tire that maintains the outer diameter of the wheel. If you buy a nice light set of forged rims (not enkei's) you could actually see an improvement in fuel economy over the heavy stockers

rpf1s are light and they are enkei's :P

[loki]

rpf1s are light and they are enkei's :P

shhhh don't let the secret out

[standsideways]

looks or performance is what u should be asking. :D

This is the truth^

18's for slightly worse performance, but "better" looks

17's ftw...get some rpf1's or another light weight wheel.

Just by getting 17's you could POSSIBLY, make your car accelerate faster, stop quicker, handle better, and get better gas mileage :P

Not like it will ever be noticable anyways lol.

17" wheels and tites are cheaper also!

[pacmann33]

Go with 17's! I went with 18ès originally and sold them after one summer, I hated the weight, and the decrease in ride comfort.

17ès that are nice and light + better performance, and better comfort....your cake that you can eat too!