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      11-24-2009, 05:45 PM   #122
ben@tirerack
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Drives: 740i
Join Date: Mar 2008
Location: South Bend, IN

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Quote:
Originally Posted by jeff4598 View Post
Just got my dunlops 235/40-18 installed and I'm amazed at the massive performance improvement (at least up to 7/10's agression)-increased torque due to smaller rear wheel,much less understeer due to more narrow rear tires, lower center of gravity due to attatchment point of suspension being 0.47 " closer to ground and with wheels at 18.5 lbs I am getting much quicker response to initial turn in and better steering feel and less steering effort , oh and the ride is more forgiving and more controled. I dont drive full out and I realize that ultimate cornering would be limited but I never get there (what % of us realy due?). Bottom line I wanted snow tires and I got a car that feels like a 911. But of course I have less ground clearance(like for snow), an inacurate speedo and an odometer that will end my warrany 4%ahead of time,higher revs at speed and of course lower gas mileage.
I'm kinda happy over all but wish I had been informed of the impact the lower rolling radius would have when I ordered the setup from Tire Rack so I could have made an informed decision.
Jeff I know we talked on the phone, but I wanted to post here for the benefit of everyone. I'm very glad to hear how pleased you are with the dry weather performance. It is often the case that a narrower width gives a little bit lighter steering feel, and going to the square setup can reduce understeer and give the car a bit more neutral feel.

With regard to fuel mileage, the reduced frontal area gives less drag, and the reduced diameter helps acceleration, but as you mention, higher revs on the highway can mean a reduction in mileage when cruising. So with more city miles it could help, more hwy miles and it could hurt. Generally fuel mileage goes down in cold weather anyway, so hard to get an apples to apples comparison.

On the dry handling side, don't everybody go buying 235's all around for your summer setup. Handling feel is *very* subjective, so not everyone will necessarily feel the same way about a given setup. Depending on how hard you push, you may feel the need for the wider widths for the dry weather. This is not to discount Jeff's experience, which is clearly very positive from a handling standpoint (and for snow too we hope ), just a word of caution that individual results may vary.
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