Tires & OEM RIMS

[RoadRunnerCincy]

I am needed new tires soon from my stock 195-50-16 dunlop 5000's. WIth gas prices moving up close to $3.00 / gal. will I lose any mileage by going with 205's on the stock rims instead? I am also considering buying a used set of stock 15's off of a LX and putting on some 205-55-15's. The DX & LX models get 3-4 MPG better mileage than the ES although there isn't much difference between the 3 models.

I have a manual and drive about 500 miles per week for my job. I have about 36k on the stock 5000's with about 2 months left on them before their done!

Also a good all-season tire that will include some winter would be welcomed.

Thanks in advance for your help.

 

[njaremka]

First - The rims on the LX / DX are four lug, the ES is five. They won't even come close to fitting.

Second - The milage difference between the LX / DX and the ES are mostly because the LX / DX has a smaller engine, unless you are comparing it with a 2.0 liter LX. The difference between the 2.0 liter LX and the ES is in the gearing. The ES has a lower final drive to provide better sporting qualities.

 

[goldstar]

The difference between the 2.0 liter LX and the ES is in the gearing. The ES has a lower final drive to provide better sporting qualities.

According to TheMAN's FAQ, all 3rd gen 2.0L engines use the G15M-R transmission. Thus, the DX, LX and ES all have the same intermediate gear and final drive ratios (4.105).

 

[goldstar]

I am needed new tires soon from my stock 195-50-16 dunlop 5000's. WIth gas prices moving up close to $3.00 / gal. will I lose any mileage by going with 205's on the stock rims instead? I am also considering buying a used set of stock 15's off of a LX and putting on some 205-55-15's.

Theoretically, switching to a 205 tire would improve your gas mileage since it has the effect of raising (numerically lowering) the final drive ratio. However, the extra weight of the 205 tire might eliminate any advantage here. According to the Miata Tire Calc, going from a 195 to a 205 tire increases the tire diameter from 23.7" to 24.1" and reduces the wheel revs/mile from 852 to 838.

I can't help you with a good all-season tire since I use summer-only tires myself and the stock Bridgestones in the winter.

Off-topic but one way to increase fuel mileage is to switch to a true synthetic engine oil and transmission oil to reduce internal engine and transmission friction. This produced a small but noticeable increase in my car.

 

[njaremka]

According to TheMAN's FAQ, all 3rd gen 2.0L engines use the G15M-R transmission. Thus, the DX, LX and ES all have the same intermediate gear and final drive ratios (4.105).

I won't get into all the errors I've found in that FAQ, but I will mention this: My workshop manual shows the 1.6 getting Mazda's F25M-R transaxel and the 2.0 getting the G15M-R transaxel.

 

[RoadRunnerCincy]

Thank you much for the replies.

"njaremka:" I hadn't noticed the 4 lug to 5 lug issue until you said it in the post. That would have been a costly oops! Thanks!

"goldstar" It's like you read my mind. I just swapped the tranny fluid the same day I posted over to Mobile 1 Full Synthetic 75 w 90. I guess I will see what I get next tank. I have also run Mobile 1 0 w20 Full Synthetic since the car had 3k on it and change the oil every 5k. I am also running Denso Iridium plugs and K&N drop on filter. My overall impression on the stock Dunlops is that they are aweful in the winter and wet but very good on dry pavement. What are others running on the daily drivers?

By the way I am most likely the oldes guy on this site. "38"

Thanks again for your help!

 

[SciFiMan]

No you're not, I'm 44 today, so I can call you a kid. (drinks)

How much winter do you get? Ice? Deep snow, or is most of your winter dry, cold roads? I have Proxes 4's now, which I love for dry and wet, but because they have problems when it's slippery or deeper snow during standing starts and going up hill (not that Chicago has any hills), this fall I'm probably switching to the Falken 512's, or maybe a winter tire like the Dunlop Winter Sport M3 or Toyo Observe G-03. I'm expecting monthly trips up to Wisconsin this winter. Then I'll get summer tires/rims in the spring.

 

[Action Jackson]

Here is a list that shows tires to fit our 16" rims:

http://www.msprotege.com/vbb225/showthread.php?t=118734

Consider skipping gears and/or short shifting to conserve gas, and keep the car well maintained.

As well, you can inflate the tires to a slightly higher pressure to decrease rolling resistence which would slightly increase fuel economy. But you may increase tire wear and change the handling of your vehicle.

I'm pretty much love using 36/34 psi F/R.

 

[RoadRunnerCincy]

No you're not, I'm 44 today, so I can call you a kid. (drinks)

How much winter do you get? Ice? Deep snow, or is most of your winter dry, cold roads? I have Proxes 4's now, which I love for dry and wet, but because they have problems when it's slippery or deeper snow during standing starts and going up hill (not that Chicago has any hills), this fall I'm probably switching to the Falken 512's, or maybe a winter tire like the Dunlop Winter Sport M3 or Toyo Observe G-03. I'm expecting monthly trips up to Wisconsin this winter. Then I'll get summer tires/rims in the spring.

"SciFiMan" Ok. I stand corrected, but will say that "we" are on the upper end of the scale here. I will look into the Falken 512's. I am still looking into going with a different set of rims "new" that would let me bump up a size to 205's and increase my mileage based on a 15" rim. I spent some time on tirerack and tire.com last night.

 

[iluvmacs]

Narrower tires are better for fuel mileage. Get some 185 or 175 profile (do 175s fit?) but you'll need a higher aspect ratio to make the diameter the same as stock. Handling will suffer, as will looks, but if this is your grocery-getter, I'd go for the mileage.

BTW, tire in the size I suggested are much cheaper, if you can find any for 16" rims. I have a set of 15" steelies from a honda accord (you need 1/4" spacers to clear the brakes) and some winter tires. You could go that route too.

 

[SciFiMan]

You're right. I have shirts older than some of these people. Although as soon as my budget allows I can start my mid-life crisis.

I switched to 205/50's a year after I got my LX and I have to say that even with an auto trans I get a consistant 29mpg year around. I think my driving habits affect my mileage way more than tire choice, although I could probably go up 1-2 mpg if I used 70K mile tires but I'd rather pay a bit more for gas. But most of my commute is highway so I'm on cruise control a lot which helps, and I check my psi every week or two to keep it spot on.

"SciFiMan" Ok. I stand corrected, but will say that "we" are on the upper end of the scale here. I will look into the Falken 512's. I am still looking into going with a different set of rims "new" that would let me bump up a size to 205's and increase my mileage based on a 15" rim. I spent some time on tirerack and tire.com last night.