Tire Size and weight load question
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Joined: Oct 2002
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From: Cottonwood, Arizona
Tire Size and weight load question
I have a 84 and changed the stock wheels to wheels from a Boxster. The Boxster's front wheel is 6" instead of 7" and the standard front tire is 205/55/16. I was going to order new tires in this size but the pros at Tirerack said that this size tire had an insufficient load capacity for the 928 so I got 225/50/16. The problem is that this tire is very close to the rim and whenever I turn the wheel and go down my driveway the tire hits the wheelwell. My questions are twofold: Do the smaller tires really have insufficient load capacity and are there any tires at 205/55/16 which have a higher load capacity?
Thanks,
ZC Wilson
Thanks,
ZC Wilson
Racer
Joined: Oct 2002
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From: Commerce, Mi
The people at Tirerack know the in and outs of tires. The handle a large majority of the performance tires for SCCA autocross racers. Unless you can find specs on the web sites for the major tire dealers, I would go with what the pros have to say.
Good luck <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />
Ell
Good luck <img src="graemlins/burnout.gif" border="0" alt="[burnout]" />
Ell
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Joined: Oct 2002
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From: Cottonwood, Arizona
I followed your advice and looked up the specifications for other tires on Tirerack. I'm afraid this time they didn't give me the best advice. There are other tires in the 205/55/16 size that have an equal load rating to the 225/50/16s. They didn't do their homework and took the easy way out. O'well, I'll just order a couple of more tires and keep the 225/50/16s for the back.
ZC Wilson
ZC Wilson
Burning Brakes
Joined: Jun 2001
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From: Herndon, VA
I'm sorry to be the one to tell you, but you should not have bought the 6" rims. Sell them and get at least 7" rims for the front and preferably with at least a 62mm offset. This is particularly important if you intend to corner rather quickly and brake rather abruptly, as would be expected at the track or even in an autocross.
Putting 225/50 tires on the 6" rim is only a band-aid solution, which can lead to a catastrophy. YMMV.
Putting 225/50 tires on the 6" rim is only a band-aid solution, which can lead to a catastrophy. YMMV.
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Joined: Oct 2002
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From: Cottonwood, Arizona
Ed, I have no intention of using my 928 for track or autocross but do you think the six inch wheel would cause me a problem in normal driving? Plus, I'm not sure I could get a seven inch wheel to match my rears.
Thanks,
ZC
Thanks,
ZC
Burning Brakes
Joined: Jun 2001
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From: Herndon, VA
If you drive like the car is made of egg shells, then 6" wheels won't be a problem. Otherwise, you made a mistake in buying Boxster wheels and not buying 928 wheels.
There are very good reasons (mostly safety related) for using 7" (or larger) wheels up front and likewise in the rear. The folks who sold you those wheels should have told you not to use them on a 928. Please don't take my message personally. I'm only trying to make you aware of the very serious problem you may encounter by overloading the tires. Also, a 225/50 tire is too wide to properly fit on a 6" rim.
YMMV.
There are very good reasons (mostly safety related) for using 7" (or larger) wheels up front and likewise in the rear. The folks who sold you those wheels should have told you not to use them on a 928. Please don't take my message personally. I'm only trying to make you aware of the very serious problem you may encounter by overloading the tires. Also, a 225/50 tire is too wide to properly fit on a 6" rim.
YMMV.
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Joined: Oct 2002
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From: Cottonwood, Arizona
Thanks, Ed, I appreciate your imput. And I don't take it personally at all. I have been a sports car person for more than 35 years but I'm new to the 928. I guess the best is to find 7" wheels for the front. (I did buy them from a person who had them on his 928 which was installed by a Porsche dealership so I just did not anticipate a problem) Thanks again.
ZC
ZC
