Vredesteins MPH
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Racer
Joined: May 2007
Posts: 346
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From: Brooklyn Michigan
Vredesteins MPH
Got a question: I just ordered some Vredesteins Sessanta's for the rear 275/35/18 and noticed according to the specs they are about an inch and an 1/8 smaller in diameter than the runcraps that went flat from sitting over the winter (Dry rot) - so I am wondering what that translates into differences in the speedometer readout? What is involved in re-calibrating to read correctly?
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From: Central Ma
Burning Brakes
Joined: Sep 2005
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From: Columbia MO
It has to take into account tire size for an accurate MPH reading. If I had a tire that was 20" tall and swapped out a tire that was 25" tall, my speedo would read way low.
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Le Mans Master
Joined: Aug 2002
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From: Norfolk VA
to the OP. You mean that a 275/35-18 is shorter than a 275/40-18
call the news media, that's a shock to everyone
Race Director
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From: San Diego CA
You should always try to stay with the factory overall diameter, within a small amount. This is especially true if you are changing only the fronts or rears, since you could be throwing off the front-to-rear height ratio.
Thread Starter
Racer
Joined: May 2007
Posts: 346
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From: Brooklyn Michigan
An FYI, after posting the original message and getting some quick responses, I was able to change my order in a nick of time to 295/35/18, which are taller and hopefully alleviate any concerns. I should have them next week. Thanks
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From: Central Ma