tire size = screwed up speedo?

[livinglegend2100]

so i just got a new set of feet and shoes on the hatchy. I went from 225/50zr15 to 235/40zr18. how much is this gonna mess with my speedo? i know in my old truck when i put bigger tires on it, the speedo was roughly 7mph off.

[ESP]

The folks over at the Miata forums built a handy little tire size conversion calculator:http://www.miata.net/garage/tirecalc.html

According to it, your new wheel/tire setup is about 1.5in greater in diameter, and that'll throw your speedo off by about 3-5mph, depending on how fast you're going.

[diggles240]

when speedo reads 60, you will actually be travelling around 64 mph. more problems if you have a/t or abs. if you have m/t, this can be corrected.

kevin

[livinglegend2100]

yea its 5spd. sounds about right though, when next to each other, the new tires are about an inch taller. i didnt measure, but, from a glance anywho.

why would i have problems with abs?

[diggles240]

if the calibration range of the abs' controller unit is exceeded then the abs system will disengage. i am not sure of the range of the s13 unit...you could still be within the acceptable range with the increase in outer circumfrance of the new tire size you have chosen....just something to be aware of.

kevin

[got chub]

ABS starts working at 7mph on the s-chassis

[adrianfromthecastle]

ABS is overrated lol

[beatd]

ABS is overrated lol

Word!

[EnjoiNismo]

ABS is overrated lol

word!except i would of liked to have it when my brakes locked up and i slid into a SUV.

[brizanden]

^yeah **** i dont even know if mine has abs or not yet

[ag240]

check your fusebox under the hood, look for one that says "abs"at least i would think that's how you would check....

easier way: go take off, then slam on your brakes

[brizanden]

^yeah thts wht people keep tellin me and im like i would prefer not to snap my neck thx. il check the fuse box tho good call. If i have abs then i have a lsd too right?

[LayNLow240]

Why not actually look for the abs modulator if your going to pop the hood? Takes like 1 second to find. It will have a ton of brake lines going into and out of it. Not that hard to spot.

[sommmatt]

ABS is overrated lol

It's so obvious you live in California.

[adrianfromthecastle]

for those that don't know if you have ABS or not..

dude... ABS sticks out like a frekkin sore thumb.

Pop your hood... if you see a thingy with a grip of metal hard lines lookin like the matrix or something... you HAVE ABS. LOL

Its not hiding like Waldo or something.

[moulton712]

just get a gps speedo.

or just put a pioneer D3 in.

[brizanden]

for those that don't know if you have ABS or not..

dude... ABS sticks out like a frekkin sore thumb.

Pop your hood... if you see a thingy with a grip of metal hard lines lookin like the matrix or something... you HAVE ABS. LOL

Its not hiding like Waldo or something.

oh it is tho... lol na ill check when i get home. bein at school 170 mi away from it sucks. i need the monies for insurance

[livinglegend2100]

ha. yea i have ABS. and btw, come live in Minnesota and tell me ABS is over-rated.... with the slew of crappy weather we get here: like snowing, raining, sleet, hail, and 100 degrees within one week, ABS is a very nice thing to have. keeps the front of my car lookin pretty.

[brizanden]

agreed no lock ups pour moi

[CRIPES]

i had a 97 GSR back in the day that i slammed into the back of a semi with b/c of ABS... you ask how in the world can a semi stop faster than a little ole sports car??? ABS. worst invention EVAR!!!

my old 96 s14 saved me from an accidnt b/c the wheels locked.. was doing 80 on the hwy and had to dig an eye lash out... next thing i saw were brake lights. EEEEERRT!!!! stopped on a dime chumps! ruined my front tires but thats cheaper to replace than my entire car... and b/c of that i got to resell her and make a grand more than what i bought it for.

abs has a big thumbs down from me....

[brizanden]

well in any conditions other then dry abs will keep most drivers from locking up and loosing control. u shoulda moved to the right (guessing u were in right lane with the semi) if u didnt think the abs was gonna let u stop fast enough which i still call

[ESP]

i had a 97 GSR back in the day that i slammed into the back of a semi with b/c of ABS... you ask how in the world can a semi stop faster than a little ole sports car??? ABS. worst invention EVAR!!!

my old 96 s14 saved me from an accidnt b/c the wheels locked.. was doing 80 on the hwy and had to dig an eye lash out... next thing i saw were brake lights. EEEEERRT!!!! stopped on a dime chumps! ruined my front tires but thats cheaper to replace than my entire car... and b/c of that i got to resell her and make a grand more than what i bought it for.

abs has a big thumbs down from me....

I hear ya!I rear ended a minivan when it came to a DEAD stop because he wasn't paying attention and slammed into a stalled car. If it hadn't been for the ABS, I would have stopped in time (although the person behind me would have rear ended me instead...). Also, I've NEVER had my ABS come on when driving through snow. Chalk that up to knowing how to drive properly for the conditions, lots of experience with non-ABS vehicles, and being incredibly alert. In a sense, I guess I'm a driving purist...all these new devices that make driving safer (and I wholeheartedly agree with that sentiment), also result in a new generation of drivers not knowing how to handle their cars should an "extreme" condition arise.

[brizanden]

^i've only felt abs come on once and i was glad it did cause i was on ice and i woulda nailed the car in front of my if it wasn't for it

[ThuG LyFe]

that mazda link is very very useful thank you.