Wheel sizes ---> speedometer adjustments

[Whistler225]

ok, does anyone know how much various non-stock wheel/tire sizes effect speedometer readings? On the same topic, it may sound stupid to some, but does anyone know how to adjust the speedo cable to compensate?

[BITESIZE]

You can't adjust the speedo. My 17's made it off by 5%. Can't remember if faster or slower. BTW, paul has a site i believe.

[cubert]

A bit off topic...but good to see a fellow NH'er on the board...


Anyway...how big of a difference is there in tire size? I go from my 17'swith low profile tires to my 15" rims with snow tires with little dif.

[paso100]

This will give you the percentage change of your speedo.
http://www.miata.net/garage/tirecalc.html

[MessyHonda]

This will give you the percentage change of your speedo.



my spedo going 1.1% and i cant feel a diference ppl should stay at a 0-5% level... ig you are going to get 17 inch rims you will have to get 205-40-17 tires

[Oldblueaccord]

Remember it not so much the rim size but the over all tire size that makes your speedo off.


wp

[forrest89sei]

ok, does anyone know how much various non-stock wheel/tire sizes effect speedometer readings? On the same topic, it may sound stupid to some, but does anyone know how to adjust the speedo cable to compensate?

when I went from a 185/70/13 to a 195/65/14 I had no problems with my speedo reading

[speedpenguin]

You should be able to get the speedo recalibrated professionally...
Not something you can do yourself, though.

[Whistler225]

Cubert: yeah, not too many 3G's on the road around here due to the salty roads...mine needs a little body work as it is. But, for 100 bucks, and it gets me back and forth to work and runs pretty darn well, I can't complain.

I think I'm going to try and find some Acura rims at the JY....or anything off an Acura or Honda really...I don't want to buy 400 dollar rims for a 100 dollar car, but I would like to replace the original hubs that came on it...

I guess if I only go to 14 or 15, it won't make enough difference for me, especially since I'm one of the only people in this state who drives at a reasonable speed ;-) I only go about 5-10 over, while everyone else does at least 15 over.....lol.

Cubert: what part of NH are you from? I'm in Concord....do you know any decent JY's around here where I can find 3G's?

[cubert]

im from nashua...and the jy i go to is in Candia...and only has one or two sadly

[bullard123]

You should be able to get the speedo recalibrated professionally...
Not something you can do yourself, though.
True, I agree with that.

[accordrollingon18z]

i have 18s with 205/35/18 tire and it didnt hurt the mileage at all

[FyreDaug]

your milage? your speedo accuracy you mean?

[FyreDaug]

ohhh I think I get it, saying youd get less milage because of the 18's turning slower.... hmm, good one

[HondaBoy]

that'd be true if the wheels large size didnt put such a load on the small engine the 3gee has. larger wheels = less engine rotation. but the how heavy they are makes a difference also. if you think about it, in the long run you'll be putting less miles on the speedo's reading with larger wheels. dont know if anyone noticed that.

[Whistler225]

yup. I did. Larger wheels= fewer wheel rotations at a given speed versus smaller wheels, therefore fewer engine/transmission rotations, so as long as your wheels aren't alot heavier than factory, I would think you'd get better gas mileage. If they're the same weight or lighter, you should get much better mileage.....

[v8vega]

that'd be true if the wheels large size didnt put such a load on the small engine the 3gee has. larger wheels = less engine rotation. but the how heavy they are makes a difference also. if you think about it, in the long run you'll be putting less miles on the speedo's reading with larger wheels. dont know if anyone noticed that.

The Effect of Wheel Inertia Weight
From HP book - Honda/ Acura Performance
On a 93 Civic Si that came with 14" wheels they put on 17" wheels with tires that had the same outside diameter. The car accelerated noticably slower. 6 hp less on a chassis dyno. The 17" wheels weighed 8 lb more and the reason the car accelerated slower is because they moved the weight farther toward the edge of the outside diameter.

[AccordB20A]

when my speedo was inaccurate i puttled it apart and moved the needle a bit lol. but now with the digi dash it have to leave it wrong