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#1
10-18-2015, 08:16 PM
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Rim size help
Due for new front tires and currently running 14 inch rims all around. 205 60 on the front and 225 60 on the back.
Any handling issues I need to be concerend with if I were to move the backs to the front and then go to a 15 inch rim on the back and use a 255 60 size? Any issues with running different size rims? Thanks, Sloan |
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#2
10-19-2015, 02:04 AM
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Rim size won't matter. I ran 14's on the front and 15's on the rear for years - although I think handling improved marginally when I finally gave up trying to find good 14" tires and made the switch to 15's all the way around.
The overall tire diameter will slightly change front end alignment as you go to a larger overall diameter rear tire. After raising the rear it would be a good idea to have the car re-aligned. Raising the rear will have a minor tendency to have the car want to turn in more on a curve, and have a little more of a tendency to wander going straight. Again, this is probably going to be such a slight change that you probably won't even notice it. This applies anytime the rears are larger than the fronts, so different size 15's front and rear would also require another alignment. Usually we go for more backspacing in the rear to properly balance the tire in the opening. Not getting the backspacing correct will plant the sidewall right up against the fender lip. Most of us end up with rims having about 5" of backspacing to have things work out correctly, but you should verify what your car wants. If someone changed rearends, that might change where the backspacing needs to end up.
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Mick Batson 1967 original owner Tyro Blue/black top 4-speed HO GTO with all the original parts stored safely away -- 1965 Catalina Safari Wagon. |
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#3
10-19-2015, 06:18 AM
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You're current tire sizes are quite small. 205/60/14's are only 23.7" tall and the 225/60/14's are just 24.6" tall.
The OE tires were about 27" tall - the same height as the 255/60/15's you are planning to put on the rear. 2.5" is a lot of difference in tire height from front to rear. I'd suggest switching the front rims to 15" at the same time and using a 235/60/15 (26.1") to lessen the height difference front to rear. 15x7" rims will work with 4.25" BS. 15x8" rims should have an extra .5" BS (half of the width difference in the rim). |
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