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Old 10-30-2012, 09:30 AM   #21 (permalink)
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Originally Posted by mrsilent13 View Post
well i am running 225 55 16 i guess going a size up on the rears and leaving the front stock would not affect it too much...or do i need to swap all 4 tires for the taller size?
Couple of thoughts:
1. Need to do 40% or more of your driving at 'cruising speed' (55-65). some members are all city driving or only drive 5-10 miles a day.
2. Usually, if you stay in the same rim size you only add 1-3 lbs of static weight. Remember, that a spinning mass is 4x the static weight. so it is a 'little' harder to get going and a 'little' more wear on suspension parts when stopping.
3. if you go up a size in rim (15 to 16) then you are possiblly adding more weight AND that weight is moved farther out on the spinning circle. Then you have to add the tire weight which is also farther out.
4. You can probably get away with a larger rear rim. Higher end cars have sensors at each axle that are thrown off with different sizes.
5. Dont forget to air up your tires 40-45psi (see posts)
6. Also look at lower rolling resistance.
7. Finally, unless you are driving 20k or more, only replace tire size as your existing tires wear out. the cost of new tires BEFORE the old ones wear out wont paybvack in the increased mileage.

I took a lot of grief for running 'cheap' Kuhmos on the infiniti forum. BUt after 5 sets I have no regrets. Once you start driving smarter, you start driving easier. Everything lasts longer! And you dont need 'high performance' parts.

MetroMPG: "Get the MPG gauge - it turns driving into a fuel & money saving game."

First: ScangaugeII

Second: Grille Block

Third: Full underbelly pan

Fourth: rear skirts and 30.4mpg on trip!
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