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Unread 06-15-2008, 10:48 PM   #1
froadin orvis
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will 31s slow down my jeep?

i've got a 95 orvis and i was wondering if or how much 31s will slow down my jeep with stock gears.

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Unread 06-15-2008, 10:49 PM   #2
cherokeeracer
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its a jeep you dont need to go fast
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Unread 06-15-2008, 10:52 PM   #3
GibsJeep
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IMO, not enough to worry about. I've got 31'' AT's on my WJ (stock geared) and I see virtually no loss of acceleration.
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Unread 06-15-2008, 10:52 PM   #4
Mr. Breeze
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Since the above is an unnecessary answer, I'll tell you that it won't affect speed or mileage very much. Not as much as 33s would.
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Unread 06-15-2008, 10:58 PM   #5
Texas ZJ1
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froading orvis,

which engine do you have? 8 or 6? The difference is that the 8 with the tow prep has the 3.73 gears and 31s will be a minimal change. However, if you have the 6 with 3.55s, you'll notice the change a lot more.

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Unread 06-15-2008, 11:00 PM   #6
GibsJeep
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I checked his Jeep info....Hes got a V8.
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Unread 06-15-2008, 11:44 PM   #7
froadin orvis
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yup, ive got the v8 with the tow pkg.
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Unread 06-15-2008, 11:49 PM   #8
anticrombie
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Uhh, duh? Of course upping tire size is going to hinder speed and acceleration.
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Unread 06-16-2008, 12:25 AM   #9
Virmagicus
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With 3.73 gears you will be just fine with 31's.
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Unread 06-16-2008, 08:22 AM   #10
j.love
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Quote:
Originally Posted by virmagicus View Post
With 3.73 gears you will be just fine with 31's.
I would have to agree. I'm running that set up and my 5.2 with 3.73 gears runs good and cruses nice at highway speeds. Plenty of power in that 5.2 to spare!
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I wouldn't drive down a driveway on that.
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Unread 06-16-2008, 09:07 AM   #11
FPKites
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You probably won't even notice it. Might see a very minimal decrease in fuel economy.
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Unread 06-16-2008, 09:22 AM   #12
nierace
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31's will increase your top speed.

(Not joking)
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Unread 06-16-2008, 09:24 AM   #13
ajmorell
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Originally Posted by nierace View Post
31's will theoretically increase your top speed.

(Not joking)
There, fixed it for you.
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Unread 06-16-2008, 01:18 PM   #14
ras2001wj
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Originally Posted by ajmorell View Post
There, fixed it for you.
But that theory has no way of being wrong........

Stock tire size fior my jeep for example: 245/70r16 has 684 revolutions per mile where as my 245/75r16 only take 662 revolutions pre mile, but with the stock gearing, the vehicle thinks it is going 60, it is really going 62 (61.98 to be exact). So say you hit your governor say set at 110 (I think thats it for WJ's, but I'm not sure, I'm not a speed demon) You are really doing 114 (113.63 before rounding up)



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Unread 06-16-2008, 01:24 PM   #15
ajmorell
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Quote:
Originally Posted by ras2001wj View Post
But that theory has no way of being wrong........

Stock tire size fior my jeep for example: 245/70r16 has 684 revolutions per mile where as my 245/75r16 only take 662 revolutions pre mile, but with the stock gearing, the vehicle thinks it is going 60, it is really going 62 (61.98 to be exact). So say you hit your governor say set at 110 (I think thats it for WJ's, but I'm not sure, I'm not a speed demon) You are really doing 114 (113.63 before rounding up)



Except that bigger tires have greater rolling resistance and therefore require more power to turn them that fast.
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