wrong tire size effect on speedometer - Honda Prelude Forum

go pre · 05-01-2002, 08:54 PM

hey.. I'm looking to get some new tires soon and I realized that the ones that came on the car when I bought it are the wrong size, 205/60/15. anyone know how much this will throw the speedo off and in which direction?

KB798 · 05-01-2002, 09:06 PM

Quote:

Originally posted by go pre
hey.. I'm looking to get some new tires soon and I realized that the ones that came on the car when I bought it are the wrong size, 205/60/15. anyone know how much this will throw the speedo off and in which direction?

wait...aren't stock rims 15"? if so then it shouldn't be a problem?

Satan_SRV · 05-01-2002, 09:07 PM

3.4% too slow

When your speedo reads 60mph you're really going 62mph

Satan_SRV · 05-01-2002, 09:08 PM

Quote:

Originally posted by KB798

wait...aren't stock rims 15"? if so then it shouldn't be a problem?

but stock tire size is 205/55/15 not 60 profile....

Tola · 05-01-2002, 09:51 PM

Here's a useful link. It should take care of all of your tire sizing:
http://autocrossing.com/cgi-bin/tiresize.cgi

If you could find it, 225/50/15 would be almost exactly stock, but you'll get a wider contact patch. From the numbers this would be the ideal size, but I've never ran it yet...

go pre · 05-02-2002, 07:30 AM

thanks for the help..

G_Loc · 05-02-2002, 03:25 PM

im running 225/50's up front cuz i didnt have enough money to get the rear ones. Car handles much better now. They dont affect the speedo either cuz at 3k im still at 60 mph and at 4k im still at 80 mph.

only problem with the tires it that they seem to egg out a bit thus looking underinflated

soopaswoze! · 05-02-2002, 11:59 PM

With my 17's my speedo has become WAY off according to those police speed thingies you drive past and they tell you speed..

usually 5+ off..

like my speedo will say 43 but the police thing will say 36-37

yet i still FLY past people when i go 5above the limit.. i dont get it.

orangecrush · 05-03-2002, 08:23 AM

that's a great little calculator. apparently, i sized just right (which is what i was hoping for).

i have 215/40/17 on mine. comparing to stock (205/55/15), i'm only -0.5% off

darkbrownmonkey · 05-03-2002, 07:35 PM

Tola, thanks for that link! I've been looking for something like that for some time now...

Satan_SRV · 05-03-2002, 08:56 PM

This one's even coola http://www.miata.net/garage/tirecalc.html nice graphics

brendon2k · 05-03-2002, 09:26 PM

Quote:

Originally posted by G_Loc
im running 225/50's up front cuz i didnt have enough money to get the rear ones. Car handles much better now. They dont affect the speedo either cuz at 3k im still at 60 mph and at 4k im still at 80 mph.

only problem with the tires it that they seem to egg out a bit thus looking underinflated

Changing the tire size won't effect the read out you get like 3k at 60 but rather 3k in 5th is not 60 like your speedo says its more like 58 or 64.