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Discussion Starter #1
I hope this ain't a dumb question...

Would I have to get my speedometer recalibrated if I went for a different size tire? According to the specs, the RPM is the same on the 255/45/17 compared to the stock 245/45/17... Yet different for the 255/40/17 (Doesn't make sence to me, I thought they'd all be different).

I checked out this site and entered the necessary info, and it told me what I thought... Both the 255 sizes were just a touch off. I put in a 275/40/17 for fun, and it was basically the same as stock (RPM).

So what do you guys think I should do, forget all this stuff and just stick with stock, or go with a touch bigger?

Will I have to recalibrate the speedo if I do change? Or is 1-2% RPM difference negligible?

Also, I was even hoping to fit 275's out back, but I don't think they'll fit... Anyone have Firehawk SZ50 EP 275's on stock 8" rims? I think the 255's should fit no prob...
 

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The 1st number is the width, second number is the sidewall hieght expressed in a percentage of the width. 255/45 would be a little taller while 255/40 would be a little smaller. As long as they are within a few % recalibrating isn't really needed and won't be noticed as you might be off 2 or 3 mph at 70 on the speedo. Just my opinion...
 
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