TIRE Q

**pajerokid** · January 22nd, 2003 10:46 PM

Guys, ano official metric equivalent ng 31" x 10.5" R15????

a) 255/70R15
b) 255/75R15
c) 260/70R15
d) 265/75R15
e) 270/70R15
f) 275/75R15

hindi po quiz to hehehe :D i tried computing for it pero ang hirap ma-determine coz the resulting figures are so close.

**afrasay** · January 22nd, 2003 10:55 PM

Mahirap yan. gagamitin ko pa utak ko. bukas na lang 10 o'clock na . GOODBYE :mrgreen:

**boybi** · January 22nd, 2003 11:00 PM

tama po si afrasay, 10 o'clock na, mahal ang overtime charge. :mrgreen:

**Ungas** · January 22nd, 2003 11:03 PM

Hmm... a tricky equation!

Pag ang habol mo yung actual diameter ng tires:

Sidewall_Radius_Diameter_Circumference_Metric Size
7.4in_14.9in_29.9in_93.9in_270/70-15
8.1in_15.6in_31.2in_98.1in_275/75-15

**pajerokid** · January 22nd, 2003 11:06 PM

ahehehehe :D Sir Alf talaga!

anyways, heto ang ginawa ko.....

* 1in = 2.54cm

31" - 15"(wheel) = 16"; (total tire dia)
16" / 2 = 8"; (sidewall length)
8 * 2.54 = 20.32cm; (sidewall in cms)
----------------------------------------------------

10.5" * 2.54 = 26.67cm (tread in cms)

----------------------------------------------------

to get aspect ratio..........

20.32 / 26.67 = 0.7619 (ANO BA ITO, 75 NA?)

----------------------------------------------------

to get tread............

*1cm = 10mm

26.67cm * 10 = 266.7mm (MGA CHONG DITO AKO NALALABUAN)

HELP!!!!!!! I just want to compute for my speedo's discrepancy since i upsized my wheels and tires. ty

hehehe 10 na nga, uwi na rin ako!!!

**Ungas** · January 22nd, 2003 11:10 PM

Pahabol out na rin ako...

check this out pajerokid:

http://www.sgmotorsports.com/tiresize.htm

Baka makatulong sa pag compute mo ng actual speed.

**kimpOy** · January 23rd, 2003 09:09 AM

buti na am ko binasa ito

the nearest possible answer is

265/75/15

dont ask why how and what?

matagal ko nang compute yan nung naka 255/70/15 pa ako

**OTEP** · January 23rd, 2003 04:08 PM

Bakit hindi mo na lang sukatin yung overall diameter using a tape measure? Madalas din namang inaccurate yung size sa side wall by 0.4"-1.0", eh.

**pajerokid** · January 23rd, 2003 06:35 PM

Otep, thats exactly the point. Hindi accurate yung "tale of the tape". Tire wear, load, air pressure, temperature and weight all play a factor in the diameter. i'd rather get the "official" size coz malamang ito ginamit ng manufacturer nung kinompyut nila yung ikot ng gulong para sa speedometer reading. :D