Copy from another car site but good info
$.02....... I like the leverage advantage that the lower (3.09) gear set gives you all the way down the track. If you have a hard time getting it to hook then you need to put more rubber on the track in addition to better weight transfer to get the job done. The biggest thing you can do to increase is more sidewall on your tire. Increasing the width of your tire is not nearly as effective as increasing the length of your footprint. The taller your tire the greater your sidewall. The smaller the diameter of your tire, the greater your sidewall. Consider this.... if your tire is 10 wide and the length of your contact patch is 2 long (like on a 20 )......you have 20 sq in of rubber on the ground. If you widen your tire out to 11.... you have increased your contact patch to 22. A whopping 2 more sq in! Increase your sidewall so that the length of your footprint is 5 (like on a 15 tire and you now have 50 sq in of rubber on the ground. Instead of a 10% increase you have a 150% increase on a narrower tire. Thats like having 5 tires back there instead of 2.
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