New wheels and tires...do i need to get my speedometer calibrated???

since i got bigger wheels and tires im hearing all this about needing to calibrate my speedometer is it really necessary???

 

Absolutely and completely necessary.

Just kidding. It might me 1-2mph off. And even that's probably pushing it. Now, your mpg might be way off from what you're used to.

 

Yea im not worried about mpg i just heard people getting pulled over for speedometer problems with new tires and wheels

 

Get an ultra Guage so you can have spot on speed and mpg.
I thought you couldn't recalibrate 2nd gens but maybe 3rd gens are different?

 

If you tell me your original tire size and new tire size I can tell you exactly how much you'll be off

 

18x9 285/65/R18

 

OK guessing by your avatar, you have a TRD Sport so original tire size was 265/65x17. Thats a 6.5% increase soo...

When your speedometer reads 10mph you'll actually be going 10.65mph
20 = 21.3
30 = 31.95
40 = 42.6
50 = 53.25
60 = 63.9
70 = 74.55
80 = 85.2

 

Oh ok after 70its the one im worried lol but thanks alot man that was alot of help

 

Unless your OK with just keeping those numbers in mind, your best solution is to get a speedometer calibrator. I think the Hypertech one is like $200

 

Ok ill check it out thanks

 

4 Wheel parts sells a plug in device that recalibrates your speedo. They said it would probably work on a 3rd gen, but hasn't been certified for it yet. I went from 245/75/17 to 285/70/17 and it was almost exactly a 10% difference. That was easy to keep track of. Someone posted a link to a site that gave you the differences between two tire sizes. I'm sure you can Google it.

 

I used http://www.rimsntires.com/specspro.jsp to calculate

 

Oorrrrrrr an ultra Guage for much less heh

http://ultra-gauge.com/ultragauge/ultragauge_wired.htm

 

Why would I want to spend money on a device that my phone can do with a free app.

 

Because you just recommended a $200 product?

And for those without an easy conversion percentage, it's nice, plus all of the other features it provides.

 

True
But that $200 device sits behind your console out of sight and automatically adjusts your OE speedometer, not add another display. I guess its just whats more important to you. Cost or Aesthetics

 

just drive and figure out what difference is and just know what speed to go.

 

My brain doesn't do math very well

 

There's a calculator on this site

 

Can you show us a pic? I'm thinking about changing my tires as well, would like to see how it looks. Thanks