odometer and non stock tires

**boybi** · August 9th, 2005 08:07 PM

Originally Posted by 111prez

teka teka, baka, now i am confused

so, to recap, change in tire size affects speedometer. that i understand from the links. sa miata.net, speedometer ang pinaguusapan.

but what about the odometer? mukhang apektado ata ang consensus. but by how much? is it the same as the effect on the speedometer?

yung engine speed or revolutions is tachometer.

but the odometer also measures total distance travelled. it is also your guide on when to do your PMS like your 5K PMS and so on

the odometer reading is derived from the tachometer and the speedometer. if you are going to know the distance travelled with non-stock tires, it will not be accurate. but for PMS purposes, you can still stick to its readings. ganun din naman kasi ang talagang tinakbo ng engine.

**Turbocharger** · August 10th, 2005 10:46 AM

San kaya pwede magpa recalibrate ng speedometer to maintain its accuracy after upgrading your stock tires?????????

**ian_rex** · August 10th, 2005 01:28 PM

sir, naisip ko lang. di naman nagbabago ang reading sa odometer, kung distance ang pinaguusapan. constant naman ang distance from point a to point b considering na nagpalit ka ng bigger rims. sample ulit. yung tranny ng civic SiR at tranny ng civic lxi iisa lang pero same ang pms nila, pero magkaiba ang rim size (13 sa lxi at 15 sa SiR) ng both.

**Loki** · August 10th, 2005 02:06 PM

Originally Posted by ian_rex

sir, naisip ko lang. di naman nagbabago ang reading sa odometer, kung distance ang pinaguusapan. constant naman ang distance from point a to point b considering na nagpalit ka ng bigger rims. sample ulit. yung tranny ng civic SiR at tranny ng civic lxi iisa lang pero same ang pms nila, pero magkaiba ang rim size (13 sa lxi at 15 sa SiR) ng both.

although they may have the same tranny, could be that distance per revolution are calibrated differently..

or..

the overall tire diameter are the same (eventhough rim size are different).

definitely the speedo and odo are both affected, but for thousand KM PMS
purposes, not significant.

**boybi** · August 10th, 2005 02:26 PM

the overall diameter of the wheel of the LXi and SiR are the same or within the threshold for accurate speedometer reading.

**Mojo** · August 10th, 2005 08:35 PM

tacho is separate sa odo/speedo cable.

yung tach is connected sa ignition system, and not sa tranny. so naka idle ka, tuloy tuloy parin yan.

apektado ang odometer/speedo accuracy pag nag palit ka ibang size na tires

**111prez** · August 10th, 2005 10:32 PM

tinanong ko rin ito dahil for purposes of computing your gas mileage, i usually use as a basis the odometer to determine my total km travelled.

so the more accurate the odometer, the more accurate the mileage computation.

to reiterate the question of turbocharger, saan kaya puede mag pa calibrate nito? or is it advisable to calibrate?

**revoGSX** · August 11th, 2005 02:29 AM

paano i-calibrate ang speedometer to reflect the non-stock tires?

**111prez** · April 21st, 2007 08:53 PM

up ko lang ulit ito

i just changed my 275/70R16 tires to 265/70R16 tires. in short, niliitan ko siya

kanina, after the tire change, wheel balancing etc, i test drove the vehicle on the skyway. at the same time, naka on rin ang GPS ko

sa speedometer reading, the needle indicated that i was running at 100kph BUT sa GPS reading i was running only at about 85kph. at the speedometer reading of 160kph, the GPS reading was only about 140kph

so which is more accurate?

:question:

**Lancie** · April 22nd, 2007 12:51 AM

mga sir, IMO lang po, the overall diameter ng gulong ng kotse ay nakaka-apekto nga pala tlga speedo/odometer reading. parang consept ng ratio.. basta! hindi ko po maexplain ng mabuti.. hehe parang ganito, 205 vs. 175.. ang 1 ikot ng 205 ay 1.3 ikot para sa 175.. kaya, masmabilis ang reading ng smaller tire diameter kesa sa bigger tire diameter.. my two cents! thanks!!!