Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Mercedes-Benz Wheels & Tires

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 07-10-2000, 12:20 AM
Subman's Avatar
Senior Member
 
Join Date: Apr 2000
Location: South Florida
Posts: 447
In the new August European Car their is an article about the trends in tire and wheel sizes (pg. 42-44). I just scaned over it but it says that skinny tires make the car handle better and that low profile tires redeuce the contact patch of the tires. And that the true bennifiets of big wheels and low tires can only be seen on the track. The article then talks about how adding big wheels to a 300E made it handle worse on the street and wonder a high speeds.
Is this true?
Has anyone expierenced wanderind after adding bigger tires on to their 300E?
Or lost handleing around town?

Their is more to this article, read it and see what you think.

Reply With Quote
  #2  
Old 07-10-2000, 04:55 AM
need2speed's Avatar
speedaholic
 
Join Date: Dec 1999
Location: Edmonton, Alberta, Canada
Posts: 1,253
There is so much physics wrapped up in tire selection that you need a Ph.D to get it even nearly right. Those of us without doctorates rely on trial and error instead. Here is what I've learned the hard way:

Lower profile tires allow quicker transient response to steering inputs. The trade-off is less sidewall flex and a harsher ride.

A larger contact patch allows for greater adhesion...to a point. When the optimum size of contact patch is exceeded, which is dependent on vehicle weight and the coefficent of friction for the road surface, you actually decrease traction by reducing the tire-to-ground loading per square inch.

Wide tires do tend to follow road surface irregularities more than narrow tires. This seems to be more pronounced on some vehicles than others, due to suspension angles. Again, there is an optimal width for each vehicle.

Of course, the manufacturer's tire size reccommendations are the safest bet and you vary from that at your own risk. Forums like this one let us share our experience with what works and what doesn't. Also, individual drivers will tolerate some trade-offs in ride harshness or tracking more than others.

And some just go for a certain look and don't really care what their beast drives like!



------------------
Dean Albrecht
94 E500
99 ML320

www.need2speed.web.com
Reply With Quote
  #3  
Old 07-10-2000, 12:27 PM
JCE's Avatar
JCE JCE is offline
Down to the Wear Bars
 
Join Date: May 1999
Location: So Kalifornia
Posts: 2,189
when it comes to tyres, a PhD in physics may be of limited help - there is often a huge gap between theory and practice. Also, the tyre compound and road/climate conditions will often have at least as great an impact as the dimensions. A "sticky" compound in a skinny tyre may outperform a wider but harder "mileage" tyre under dry conditions, but may not do as well under wet conditions. There is are way to many variables here for a blanket, rule of thumb to always hold true

------------------
JCE
87 300E, 65k miles
Smoke Silver
Reply With Quote
  #4  
Old 07-10-2000, 01:00 PM
Registered User
 
Join Date: Aug 1999
Location: ajax, ontario, canada
Posts: 773
i've been following the series of articles of the European Car magazine on suspension basics up to a few months back, and handling is only part of the story, and tires do play a role in this. The current issue of European Car contains the 6th in the suspension series, if i remember.

following are other points on the use of low-profile tires on road and track:

- lower profile tires (again, all other factors being equal) tend to have a more sudden breakaway when cornering. Higher-profile tires give you lots of warning. Race drivers have the reflexes to deal with the sudden breakaway.

- given a tire's rolling diameter or the car's wheel well size, a racing car would tend to use the largest wheel possible, simply to accommodate the biggest brakes possible. This means having the lowest profile possible. Ride quality is way down on their list of priorities.

- wide and low-profile tires tend to be more sensitive to camber change as the suspension moves, as it significantly affects the shape of the contact patch.

Passenger cars have a lot of wheel travel for comfort and ground clearance, and allow for some amount of body roll. Compared with a race car, the changes in tire camber of a passenger car (due to suspension geometry and body roll) are significant. Mercedes cars, in particular, traditionally have lots of body roll, although its suspensions generate some negative camber as they compress to counteract this. As a result, passenger tires are of the higher-profile variety, which can accommodate a wide range of camber change.

Race car suspension on the other hand is very stiff and roll is minimal, and wheel travel and camber are tightly controlled, allowing for precise suspension tuning. Another reason for the stiff suspension is to accommodate the significant downforce generated by the aero aids.

- a minor tradeoff is frontal area of the tire - wider tires generate more drag, but this can be reduced by fairings (which reduce the drag coefficient) or lowering the car (which reduces the exposed frontal area of the tire).

For curb appeal, a low-profile tire definitely looks better, but pizza-sized brake rotors are definitely sexier.
Reply With Quote
  #5  
Old 07-10-2000, 09:32 PM
Registered User
 
Join Date: Feb 2000
Location: Toronto, Ontario, Canada
Posts: 14
Very good comments. Like most motorheads, I just assumed that the lower profile and more grip tire the better. The closest that I come to a track is the highway commute. I have a 99 C230 Kompressor and upgraded to 16 inch rims with a wider track at the rear. They run on Pirelli P7000. These tires are excellent in the rain. However, on the highway they wander a lot. In fact, it can tiring on a long trip as it requires a lot of concentration to keep the car in a straight-line. In fact, this is so bad that I am going to have MB check the alighment and tire balance even though the car is relatively new.

Given what I have learned from these comments, I will seriously reconsider upgrading to a lower profile tire on my next MB. I think the comments about MB's steering and suspension on lower profile tires are correct. I did not experience this wansdering problem on other automobiles. I had a 98 Volvo S70 with lower profile tire and did not experience such steering problems.
Reply With Quote
  #6  
Old 07-11-2000, 12:11 AM
Registered User
 
Join Date: Mar 1999
Location: Atlanta, Georgia, USA
Posts: 1,342
In my experience, you can usually go significantly wider than MB OEM on many models without too many problems. The 300E does very well on OEM's but can be sharpened significantly by just sportline sizes. A 400E overwhelms the OEMs and does okay on Sportline sizes but really shines in the plus 1 fittment. 500E's can really overwhelm the stock fare but do great on plus 1's. The newer cars came with a more aggressive fittment from the factory so you see a less dramatic improvment than the older cars in my opinion. Unless you've done significant suspension work more than a plus 2 wheel/tire combo will not help handling. If your going for cosmetic appeal its great, if its more performance then it can vary some. Then again, beauty is in the eye of the beholder... Know your priorities going into an upgrade, get all the info you can, then do what (by all your info) seems to be the best option. Of course, talking to the folks in this forum and Luke ALWAYS helps.

Lee
Reply With Quote
  #7  
Old 07-15-2000, 12:28 PM
Registered User
 
Join Date: Apr 2000
Posts: 530
I disagree on the 400E. I think it shines best in its TRUE plus 0 fittment. 215/60/15. Best feeling one I've ever driven had that WITH 7" rims. That is a necessity. This combo sucks on 6.5" rims.

Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Tire Tech Luke@tirerack Mercedes-Benz Wheels & Tires 3 12-13-2006 03:32 PM
Stuff that makes you wonder. Post your pictures!! Cap'n Carageous Off-Topic Discussion 88 11-01-2003 03:15 PM
Winter wheel and tire packages .............. Luke@tirerack Mercedes-Benz Wheels & Tires 0 09-26-2003 10:36 AM
Wheel Tech .... from The Tire Rack Luke@tirerack Mercedes-Benz Wheels & Tires 0 02-28-2003 02:52 PM
Big Trouble! Wheel locks stripped and flat tire Johnson Chan Mercedes-Benz Wheels & Tires 9 11-22-2002 07:55 PM



All times are GMT -4. The time now is 06:18 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page