running thinner tires than stock
Thread Starter
Senior Member
Joined: Dec 2016
Posts: 343
Likes: 43
E250 Diesel
running thinner tires than stock
for my winter set up (finally doing some road trips out of the warm Los Angeles area) I thought I could go with 225's instead of the 245's, which is stock. It will 50 profile instead of the 45 profile.
I thought the stock wheel width is 8 inches and should be fine for the 225's. And the speedometer error should be within 1% (the stock set up overstates the speed anyway....)
conventional wisdom is to go just a bit narrower on width and higher on profile for the all-season or winter set up. but I just wanted to throw it out there to see what you all are running for the winter.......
I thought the stock wheel width is 8 inches and should be fine for the 225's. And the speedometer error should be within 1% (the stock set up overstates the speed anyway....)
conventional wisdom is to go just a bit narrower on width and higher on profile for the all-season or winter set up. but I just wanted to throw it out there to see what you all are running for the winter.......
Super Member
Joined: Feb 2011
Posts: 507
Likes: 16
'11 E350BTC P2 Leather
I am running 225/45R17 run flat snows (Blizzak LM-25) while the non snows are 235/45R17
According to Waze, the speedometer is within 1mph, and everything's great.
A little less width is not a problem in the winter.
(for me the run flat snows didn't come in a 235)
According to Waze, the speedometer is within 1mph, and everything's great.
A little less width is not a problem in the winter.
(for me the run flat snows didn't come in a 235)
Senior Member
Joined: May 2016
Posts: 397
Likes: 32
From: California
2016 E 250 Bluetec
for my winter set up (finally doing some road trips out of the warm Los Angeles area) I thought I could go with 225's instead of the 245's, which is stock. It will 50 profile instead of the 45 profile.
I thought the stock wheel width is 8 inches and should be fine for the 225's. And the speedometer error should be within 1% (the stock set up overstates the speed anyway....)
conventional wisdom is to go just a bit narrower on width and higher on profile for the all-season or winter set up. but I just wanted to throw it out there to see what you all are running for the winter.......
I thought the stock wheel width is 8 inches and should be fine for the 225's. And the speedometer error should be within 1% (the stock set up overstates the speed anyway....)
conventional wisdom is to go just a bit narrower on width and higher on profile for the all-season or winter set up. but I just wanted to throw it out there to see what you all are running for the winter.......
A word of advice, if you want a higher profile tire you dont necessarily have to go narrower. I would recommend going with 255/45. This way you are a tad bit wider than stock and you will have even MORE tread than a 225/50 tires.
225/50 tires = 4.4" of rubber
255/45 tires = 4.5" of rubber
Thread Starter
Senior Member
Joined: Dec 2016
Posts: 343
Likes: 43
E250 Diesel
yes. Winter set up. (Though in southern CA, we r dealing mostly with rain with occasional trips to snow bound regions). I'd probably stick with 225's.
Senior Member
Joined: Aug 2014
Posts: 255
Likes: 36
From: Las Vegas
2012 E350 sedan
Trending Topics
Thread Starter
Senior Member
Joined: Dec 2016
Posts: 343
Likes: 43
E250 Diesel
I stand corrected on my stock wheel width. as it turns out it may be 8.5 inches wide. I could have sworn it was 8 inches but I really can't tell for sure. I looked at the wheel but it doesn't say on the wheel itself. the manual says both 8 inches and 8.5 inches.
It's a bit of an issue because I don't want to put on 225's on 8.5 inch wide wheels. Anyone know for sure?
I think the part number is: 2124015902
It's a bit of an issue because I don't want to put on 225's on 8.5 inch wide wheels. Anyone know for sure?
I think the part number is: 2124015902
MB World Stories
The Best of Mercedes & AMG
8 Oddball Mercedes Ideas That Actually Made it to Production
Verdad Gallardo
Dubai Tuner Gives the Mercedes G-Class An Entirely New Look
Verdad Gallardo
Six Gift Ideas Your AMG Loving Dad or Grad Will Cherish
7 Craziest Things AMG Gas Ever Built
Verdad Gallardo
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know
Verdad Gallardo
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Super Member
Joined: Dec 2010
Posts: 746
Likes: 26
None
Super Member
Joined: Dec 2010
Posts: 746
Likes: 26
None
While you are correct that a smaller contact patch means greater weight per square inch, you incorrectly assume that a skinnier tire results in a smaller contact patch. It does not, unless you increase tire pressure.
At 35 psi, a skinnier tire will just have a thinner, but longer contact patch than a wider tire.
3500lb car, 35 psi tire pressure, means 100 square inches of contact patch, regardless of tire width. It's just math.
You are welcome for the insight.
Last edited by looney100; Feb 14, 2017 at 11:06 PM.
Super Member
Joined: Dec 2010
Posts: 746
Likes: 26
None
Banned
Joined: Oct 2005
Posts: 4,957
Likes: 1,640
So strong, so wrong.
While you are correct that a smaller contact patch means greater weight per square inch, you incorrectly assume that a skinnier tire results in a smaller contact patch. It does not, unless you increase tire pressure.
At 35 psi, a skinnier tire will just have a thinner, but longer contact patch than a wider tire.
3500lb car, 35 psi tire pressure, means 100 square inches of contact patch, regardless of tire width. It's just math.
You are welcome for the insight.
While you are correct that a smaller contact patch means greater weight per square inch, you incorrectly assume that a skinnier tire results in a smaller contact patch. It does not, unless you increase tire pressure.
At 35 psi, a skinnier tire will just have a thinner, but longer contact patch than a wider tire.
3500lb car, 35 psi tire pressure, means 100 square inches of contact patch, regardless of tire width. It's just math.
You are welcome for the insight.
Super Member
Joined: Dec 2010
Posts: 746
Likes: 26
None
Skinnier tires have always been better in snow than wide fat tires because they cut through the top layer to get traction and don't ride on top of it. More pressure bearing down from a smaller footprint. Simple math. Would you rather use a steak knife on your steak or a butter knife? This whole tread is about a skinny tire vs wider tire in snow.
Your knife analogy is not appropriate as a steak knife has a sharper blade - a much finer point than a butter knife. Less surface area means more pressure, which improves cutting ability. A serrated edge further reduces surface area and improves cutting by increase the pressure. Same weight on few square inches. Which is not what happens with tires.
Thread Starter
Senior Member
Joined: Dec 2016
Posts: 343
Likes: 43
E250 Diesel
I don't know about the all these physics stuff but rally car people have to run skinnier tires than road race people - wider tires transmit every little bump and gravel. Snow traction is better too. I'm told they run about 185 to 205 for dirt, water and snow. See this vid. and see how thin the tires are.
Formula 1 teams also typically run rain tires that are tiny bit narrower than full dry tires (though this may be limited by restriction put on by F1). see this comment from Pireli about needing narrower tires in the wet condition. http://www.f1fanatic.co.uk/2017/01/1...weather-tyres/
Formula 1 teams also typically run rain tires that are tiny bit narrower than full dry tires (though this may be limited by restriction put on by F1). see this comment from Pireli about needing narrower tires in the wet condition. http://www.f1fanatic.co.uk/2017/01/1...weather-tyres/
Super Member
Joined: Dec 2010
Posts: 746
Likes: 26
None
I don't know about the all these physics stuff but rally car people have to run skinnier tires than road race people - wider tires transmit every little bump and gravel. Snow traction is better too. I'm told they run about 185 to 205 for dirt, water and snow. See this vid. and see how thin the tires are. https://www.youtube.com/watch?v=RBXB...eature=related
Formula 1 teams also typically run rain tires that are tiny bit narrower than full dry tires (though this may be limited by restriction put on by F1). see this comment from Pireli about needing narrower tires in the wet condition. http://www.f1fanatic.co.uk/2017/01/1...weather-tyres/
Formula 1 teams also typically run rain tires that are tiny bit narrower than full dry tires (though this may be limited by restriction put on by F1). see this comment from Pireli about needing narrower tires in the wet condition. http://www.f1fanatic.co.uk/2017/01/1...weather-tyres/
There could also be specifics related to the setup of the rally cars, need for much greater lateral bite and surface conditions that might make thinner tires favourable.
If if you go back to my initial points. They were that a thinner tire does not decrease the contact patch, nor increase the pressure on the road. These two points are simple math.
On the broader question of are thinner tires better in the snow - they could be under certain circumstances - particularly at higher speeds and if Snow cover is light and getting tire contact with good Pavement is possible.
