Replacement tires for Saturn SW2 - Fuel Economy, Hypermiling, EcoModding News and Forum

pete c · 09-08-2012, 05:17 PM

My daughter's SW2 is in bad need of a new pair of shoes. I was thinking of replacing the stock 185/65/15s with something a bit taller/narrower.

Does anyone out there have experience with this? CarloSW2, yeah, i'm tawkin' to you! Or anybody else that has an S series saturn.

I am thinking that a 185/70 or maybe a 175/75 might work. Being a twin cam, it has the shorter gearing and could easily handle the higher final drive ratio. My daughter learned to drive stick with this thing and it is ridiculously easy to launch. Much easier than my wife's '09 Sonata 5 speed.

mcrews · 09-08-2012, 08:01 PM

Just me, but I wouldn't narrow a tire on my daughter's car for a 50% increase in mileage.
but that's just me.

Taller I'm ok with.
LRR is ok.

Come on. It's your daughter.

pete c · 09-08-2012, 08:58 PM

I am not talkingabout much narrower. No smaller than 175. i don't believe there is any compromise in safety. In fact, a slightly narrower tire may reduce the chances of hydroplaning and would do better in snow. Yeah dry lap times might drop a few tenths, but, that is not a concern. If she was a 20 year old guy, it would be.

CapriRacer · 09-09-2012, 08:54 AM

First, I don't think you'll find anything narrower in a 15". (I'm assuming you don't want to change wheels)

Second, I wonder why you would want to make this change. In the case of fuel economy, bigger is better - and by bigger I mean any of the 3 numbers used to determine tire size.

Besides, the difference between tires is SOOOO much larger than the difference between sizes. Careful selection of the tire (meaning make and model) is THEE most important thing.

pete c · 09-09-2012, 09:27 AM

Quote:

Originally Posted by CapriRacer

First, I don't think you'll find anything narrower in a 15". (I'm assuming you don't want to change wheels)

You assume correctly.

Quote:

Second, I wonder why you would want to make this change. In the case of fuel economy, bigger is better - and by bigger I mean any of the 3 numbers used to determine tire size.

Have to disagree with this. A narrower tire would be preferrable, I think. Of course, you do need to go to a higher profile to maintain or increase tire diameter. And increased sidewall height could possibly increase RR.

quote]Besides, the difference between tires is SOOOO much larger than the difference between sizes. Careful selection of the tire (meaning make and model) is THEE most important thing.[/QUOTE]

This is true. Any suggestions?

CapriRacer · 09-09-2012, 10:07 AM

Quote:

Originally Posted by pete c

.....Have to disagree with this. A narrower tire would be preferrable, I think. Of course, you do need to go to a higher profile to maintain or increase tire diameter. And increased sidewall height could possibly increase RR.

.....

Barry's Tire Tech

I was surprised by this as well, but that is what the data says.

Quote:

......This is true. Any suggestions?

Sorry, but my expertise is in the engineering of tires, not cataloging differences.

pete c · 09-09-2012, 01:21 PM

Very nice site you have there.

So, it looks like the answer to my question is go with the biggest LRR tire I can fit. I think I will probably go with a 205/65 or 60. I believe it will fit. I will check over at the saturn forum.

arcosine · 09-09-2012, 03:53 PM

I have 205/70R15 on my saturn, that's the tallest tire that fill fit without rubbing on the front strut spring seat, and the clearance is very small. You won't find a 70 series tire smaller than 205 in a 15 inch wheel. I have had 165/80R15 on, the handling is not as good with the skinny 80 series, but they go through standing water just great. You should stick with the 185/65R15 or one size bigger.