Getting new tires?

[RDedrick]

I knew there is a post on here some where that tells me this, but I can not find it. I am going to get some BFG 285/70/17 KO put on tomorrow. I have 265/70/17 on now. I was wondering how bad this will affect my speed odometer? I know somebody posted a place to go that would calculate this.

 

[AndyMan]

RDedrick,



I can't answer your question, although I can say that a search should net you the information that you're looking for. My gut feel is that size difference is neglegable.



Also, I want to invite you to step over in the Mid-Tenn Chapter Roundtable and say hello!! We're always looking for new people in the area. We're about 25 TDR members strong or so. Matter of fact, we're having an informal get together next Friday (everything TBD at the moment). We'ed love to have you there with us!!



Check us out here: https://www.turbodieselregister.com/forums/forumdisplay.php?f=136

EDIT: The roundtable is a 42 Page thread, so you might want to just skip straight to the last page!!

 

[AMink]

http://www.miata.net/garage/tirecalc.html



Here's one link.

Specification Sidewall Radius Diameter Circumference Revs/Mile Difference

265/70-17 7. 3in 15. 8in 31. 6in 99. 3in 638 0. 0%

285/70-17 7. 9in 16. 4in 32. 7in 102. 8in 617 3. 5%

You would have a 3. 5% difference. When your speedo says 60, you'll be doing 62. 1. Not too big a difference.

 

[1Tufdsl]

I used the same link that Amink referenced before I bought my 285's but when I used my GPS after they were on I was about 5 mph off. The dealer can quickly recalibrate the speedo by entering the new rev's per mile of the 285's. The link in my sig has some pic's with the 285's on.

 

[RankRam]

1Tufdsl thanks for the link to your pics. I'm thinking that 285's are the way to go for someone that tows and has 3. 73's.

 

[klenger]

This might help



http://www.klenger.net/dodge/general-reference/gear-speed-calculator.xls