speedometer calculator
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speedometer calculator
I've seen this on here before...
anyone have the link to see how much your speedometer will be off by changing tire size?
I have a 1998 expy with factory tires and rims, the 17" rim - changed to 305/45/22 - also do I need to get the transmission re-programmed for shift points? I don't go off-road, I don't tow, I don't drive up mountains -
Thanks... any help is appreciated!
anyone have the link to see how much your speedometer will be off by changing tire size?
I have a 1998 expy with factory tires and rims, the 17" rim - changed to 305/45/22 - also do I need to get the transmission re-programmed for shift points? I don't go off-road, I don't tow, I don't drive up mountains -
Thanks... any help is appreciated!
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Joined: Nov 2002
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From: Central Mass.
http://www.miata.net/garage/tirecalc.html~~~~~~~~~~~~When your speedo says 60 you will actually be at 62.3 mph. You probably won't notice a thing. Tranny will shift per rpm and now your rpm will take a little longer to get to that spot.
Last edited by tonum24; Dec 13, 2003 at 04:42 PM.
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From: San Rafael, NM
width = 265/25.4=10.43
10.43 X .70=7.30
7.30 X 2=14.60
diameter = 14.60 + 17=31.60
Your tires were (d=31.60") X (w=10.43")
PS To figure out the the speedometer change just devide the circumference[C = d X 3.14] of your new tires by the circumference of your old tires, then multiply that number by what your speedometer is reading and that will give you your actual speed.
10.43 X .70=7.30
7.30 X 2=14.60
diameter = 14.60 + 17=31.60
Your tires were (d=31.60") X (w=10.43")
PS To figure out the the speedometer change just devide the circumference[C = d X 3.14] of your new tires by the circumference of your old tires, then multiply that number by what your speedometer is reading and that will give you your actual speed.
Last edited by damonlan; Dec 13, 2003 at 08:53 PM.
