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Discussion Starter #1
I put a set of goodyear brand 235-55-17 on my GTO they are 27.20 inches tall and fit nicely. No more wheel spin as with the 245"s and the acceleration it great. There is an obvious gear ratio change with this tire Im guessing in 3.30 range but the car seems to like it. I will do some drag strip test soon. Im curious as to how this gear change will affect my ET's my last run was 13.27 at 106 so Im thinking I will have a slower ET but a higher MPH. I saw this size tire on the newer style Mustangs and figured since the price was right $50.00 for both I would give them a try.-----Danfigg
 

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Interesting idea. Your speed should be off about 5% (indicated lower than actual) and your gearing is around an effective 3.28 instead of 3.46. You actually lost a small amount of contact patch and may have a better launch due to the gearing change preventing you from spinning and differing rubber compound may explain differences as well. I commented on my 3.46 gears both helping and hurting as it makes it too easy to spin on launch. The higher sidewall can help cushion the "shock" as well.
 

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Discussion Starter #3
re

Svede you hit it on the head that is why I thought of trying this. Not much change in handling, and the rake is some what interesting I will try to post some pics soon. I will also try them on the front to see if they fit as well.The tire seems to be wider as you look from the back but according to tire rack the 235-55-17 are 9.7" 8.1" 27.2" 769---the 245-45-17 are 9.4" 8.3" 25.8" 808
section width -tread width -overall diameter -REV per Mile
 

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Discussion Starter #4
re

Just checked the 235 -50 -17 is a better fit its wider 9.7" 8.5" 26.3" 792
 
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