Narrower tires
- Thread starter tigrpal
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Your tire "footprint" would be slightly smaller.
The gain/loss for handling, ride, snow performance, etc., would be minimal.
The gain/loss for handling, ride, snow performance, etc., would be minimal.
Your speedometer is probably collaborated for the factory fitted tires your car came with. If you install the 185's, your speedometer will read 2% too fast. The 185's will also turn more revolutions per mile than the 195's. The 195's will give you a bit more cushier ride to due to a larger sidewall.
Here is all the info you need. http://www.miata.net/garage/tirecalc.html
Here is all the info you need. http://www.miata.net/garage/tirecalc.html
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Mostly insignificant.
what about if I went from 155 80 R13 to 175 70 R13. i expect better handling and stopping distance, possibly slightly less mileage, but more unsprung weight, at the level of the tire tread - and what effect would this have on the compliance of the suspension, cushiness of the ride etc?
Originally Posted By: scoobie
what about if I went from 155 80 R13 to 175 70 R13. i expect better handling and stopping distance, possibly slightly less mileage, but more unsprung weight, at the level of the tire tread - and what effect would this have on the compliance of the suspension, cushiness of the ride etc?
Since the tire sidewall height will remain practically unchanged, I wouldn't expect much difference in terms of handling or ride comfort.
By handling I mean steering response. To improve steering response, you would need shorter sidewalls, which in your case would mean upgrading to larger rims. Shorter sidewalls also result in more firm/stiff ride.
A lot also depends on a specific tire model - some are stiffer than others in the same size.
what about if I went from 155 80 R13 to 175 70 R13. i expect better handling and stopping distance, possibly slightly less mileage, but more unsprung weight, at the level of the tire tread - and what effect would this have on the compliance of the suspension, cushiness of the ride etc?
Since the tire sidewall height will remain practically unchanged, I wouldn't expect much difference in terms of handling or ride comfort.
By handling I mean steering response. To improve steering response, you would need shorter sidewalls, which in your case would mean upgrading to larger rims. Shorter sidewalls also result in more firm/stiff ride.
A lot also depends on a specific tire model - some are stiffer than others in the same size.
Originally Posted By: tigrpal
2007 Corolla LE came with P195/65R15 tires. Owners manual says I can use P185/65R15. What would I gain and what would I lose by going to the narrower tread? Or would it be insignificant?
I think you'd definitely notice less dry traction (lower cornering and braking limits). 10mm out of less than 200mm is a lot.
On the other hand, you would also get slightly better mileage, and the car would perform a little better in deep standing water or snow. You might also get slightly less tire noise.
IMO, the choice depends on your driving style. If you're a very mild driver and don't drive often on the highway, you might want to consider the narrower tire, although I'd recommend a higher profile (185/70R15). Otherwise, stick with 195.
2007 Corolla LE came with P195/65R15 tires. Owners manual says I can use P185/65R15. What would I gain and what would I lose by going to the narrower tread? Or would it be insignificant?
I think you'd definitely notice less dry traction (lower cornering and braking limits). 10mm out of less than 200mm is a lot.
On the other hand, you would also get slightly better mileage, and the car would perform a little better in deep standing water or snow. You might also get slightly less tire noise.
IMO, the choice depends on your driving style. If you're a very mild driver and don't drive often on the highway, you might want to consider the narrower tire, although I'd recommend a higher profile (185/70R15). Otherwise, stick with 195.
If you go narrower you lose "unsprung" weight on the wheel. So the less weight on the wheel the easier it is for the motor to turn it. Thus better MPG and performance(fractions better in theory)
But with the wider tire, you have better contact to the ground, so you get better traction, more grounded turning, and more bite when stopping.
Between the two and there pros/cons, you would need a computer to get the fractional differences in both tires.
But with the wider tire, you have better contact to the ground, so you get better traction, more grounded turning, and more bite when stopping.
Between the two and there pros/cons, you would need a computer to get the fractional differences in both tires.
Originally Posted By: ksJoe
Aren't wider tires more prone to hydroplaning have worse snow traction?
That can be a factor. But with todays tire treads, so much money has gone into R&D, I would feel very safe running a wider tire now.
Aren't wider tires more prone to hydroplaning have worse snow traction?
That can be a factor. But with todays tire treads, so much money has gone into R&D, I would feel very safe running a wider tire now.
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Aren't wider tires more prone to hydroplaning have worse snow traction?
Re wider tires: Depends on the thread design. Some do better than others in standing water. You just drive accordingly when you find the new tires limits. Having run Daytons, Firestones, BFG's in the same size, each tire behaves a bit differently. Worse than a narrower tire? Not necessarily. Comes back to the thread design.
Re snow traction: Thats a personal decision to make. I prefer wide and floaty so I don't dig down to the ice hiding below. I've run narrow and wide on/off over the years. Narrow never fails do dig me down in parking lots giving me more work. On the other hand, if punching drifts, the wide tires require much more due dilegance at the steering wheel. So depending on what you are driving through I'd let that sway your opinion on which snow tire school of thought to follow.
Alex.
Aren't wider tires more prone to hydroplaning have worse snow traction?
Re wider tires: Depends on the thread design. Some do better than others in standing water. You just drive accordingly when you find the new tires limits. Having run Daytons, Firestones, BFG's in the same size, each tire behaves a bit differently. Worse than a narrower tire? Not necessarily. Comes back to the thread design.
Re snow traction: Thats a personal decision to make. I prefer wide and floaty so I don't dig down to the ice hiding below. I've run narrow and wide on/off over the years. Narrow never fails do dig me down in parking lots giving me more work. On the other hand, if punching drifts, the wide tires require much more due dilegance at the steering wheel. So depending on what you are driving through I'd let that sway your opinion on which snow tire school of thought to follow.
Alex.
I still think narrow is probably a bit better. Go look at the World Rally Cars for snow events. Those Pirelli's are SKINNY. Look like Donut Spares almost.
235/40 - 18 (tarmac)
205/65 - 15 (gravel)
145/85 - 16 (ice)
are the spec sizes for crying out loud. Must be something to it.
235/40 - 18 (tarmac)
205/65 - 15 (gravel)
145/85 - 16 (ice)
are the spec sizes for crying out loud. Must be something to it.
But they also run them studded, which changes things a bit.
Well, none of the tires discussed here are considered wide. Even 205's aren't considered wide. It also depends on the profile of the tire. Some 195's are wider and some are narrower.
tigrpal,
The 195's on your Corolla are just fine. You will loose ride height by dropping down to 185-65-15 and therefore, deep snow might give you a bit of trouble. A 185-70-15(if this size is even produced) would be a jump up from a 195-65-15 and should do quite well in the deep snow. Here's the overall diameter of these three sizes:
195-65-15 = an overall diameter of 24.98" **=
185-70-15 = an overall diameter of 25.19" **>
185-65-15 = an overall diameter of 24.47" * I would stay with the 195's.
tigrpal,
The 195's on your Corolla are just fine. You will loose ride height by dropping down to 185-65-15 and therefore, deep snow might give you a bit of trouble. A 185-70-15(if this size is even produced) would be a jump up from a 195-65-15 and should do quite well in the deep snow. Here's the overall diameter of these three sizes:
195-65-15 = an overall diameter of 24.98" **=
185-70-15 = an overall diameter of 25.19" **>
185-65-15 = an overall diameter of 24.47" * I would stay with the 195's.
Thanks for the info. Not sure if I'll go narrower or not. Most people on the forums are always asking about going wider so I was wondering. I don't drive aggressively at all so handling wouldn't be much of a concern. Some snow here in the Chicago suburbs but the streets are plowed pretty well. I may consider it for the gas mileage. My speedometer already is 2-3 mph above the actual speed at least according to my Scangauge.
It's interesting that the CE model of the Corolla, the cheaper model (didn't have power door locks or power windows etc.), came standard with the 185's. MPG was rated the same.
It's interesting that the CE model of the Corolla, the cheaper model (didn't have power door locks or power windows etc.), came standard with the 185's. MPG was rated the same.
Originally Posted By: tigrpal
It's interesting that the CE model of the Corolla, the cheaper model (didn't have power door locks or power windows etc.), came standard with the 185's. MPG was rated the same.
Because the difference won't be big enough to affect fuel economy by a whole extra mile per gallon, which is what we've been trying to tell you - the difference will be insignificant.
It's interesting that the CE model of the Corolla, the cheaper model (didn't have power door locks or power windows etc.), came standard with the 185's. MPG was rated the same.
Because the difference won't be big enough to affect fuel economy by a whole extra mile per gallon, which is what we've been trying to tell you - the difference will be insignificant.
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My speedometer already is 2-3 mph above the actual speed at least according to my Scangauge.
Smaller tires will mean your speedo will read even faster (in this case, only 1.2mph).
What does the scan guage reference road speed to? Got a gps to confirm?
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the difference will be insignificant.
10-4.
Mathematically:
.4" narrower (thats 4/10ths of an inch)
.5" shorter (1/2") UNLOADED diameter. Play with tire pressure and you will make a bigger difference.
Alex.
My speedometer already is 2-3 mph above the actual speed at least according to my Scangauge.
Smaller tires will mean your speedo will read even faster (in this case, only 1.2mph).
What does the scan guage reference road speed to? Got a gps to confirm?
Quote:
the difference will be insignificant.
10-4.
Mathematically:
.4" narrower (thats 4/10ths of an inch)
.5" shorter (1/2") UNLOADED diameter. Play with tire pressure and you will make a bigger difference.
Alex.
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