Odometer Miles with bigger tires

[frontierguy25]

I have a question for you guys, I have 275/40/17 BFG Gforce Sports, and I went on a trip to a couple of my stores and Mapquest and google maps said it was about 365 miles when I got home from the trip my odometer said that I had only gone 339 miles. Just trying to figure out why my odometer might be off a little bit? If it is off, is this throwing my speedo off as well?

I'm doing this same trip tomorrow and just wanted to know about my mileage.
Thanks

 

[gaboonviper85]

yes your speedO is incorrect...as majority of ours are....BUT bigger tires will also effect speedo readings...with a larger tire, you'll cover more area per revolution...

 

[gaboonviper85]

so yes I'd expect to see less miles shown on a mechanical od...and if your speedo was correct then you'll be going a few mph faster then what it reads...

 

[frontierguy25]

Great thanks, So I'm getting a little better gas mileage than I thought that I was. I'm driving my car all over with the new job of mine.

 

[gaboonviper85]

Great thanks, So I'm getting a little better gas mileage than I thought that I was. I'm driving my car all over with the new job of mine.

oh don't put words in my mouth...didn't say your getting better gas milage...bigger tires are harder to turn remember....if that was the case I'd go out and put some wicked farm tractor tires on my car.

Think of it like a speed bike...the gear that makes you go the fastiest is also the hardiest to pedal...

 

[webbs7mgte]

very wise gaboon very wise..words fo wisdom

 

[gaboonviper85]

ps...like the sig!

 

[IJ.]

The longer at cruise speed you are the more fuel you'll save but the taller gears will need more throttle % to move the car so stop start driving will hurt economy.

 

[frontierguy25]

My bad I should've clarified myself. I meant because the odometer is only showing like 300 miles and I have actually gone 330 miles, I'm getting a little better mileage than what the car shows.

I know all about bigger tires, shoot I haven't run anything smaller than 275's since I got the car 9 years ago. Just lighter wheels.

 

[IJ.]

Yep your calcs need to be on actual mileage
(I think the sig was meant to read "rampant")

 

[frontierguy25]

ps...like the sig!

That thread was starting to piss me off and when you said that, I fell over laughing so hard.

IJ. The longer at cruise speed you are the more fuel you'll save but the taller gears will need more throttle % to move the car so stop start driving will hurt economy.

I have 3:73's with a 5 speed, so that is cool with me. My mileage driving around city sux with these 660 injectors, but hey that's what you get when having fun!!:naughty:

 

[gaboonviper85]

My bad I should've clarified myself. I meant because the odometer is only showing like 300 miles and I have actually gone 330 miles, I'm getting a little better mileage than what the car shows.

I know all about bigger tires, shoot I haven't run anything smaller than 275's since I got the car 9 years ago. Just lighter wheels.

still don't under stand the "better" part....your not getting better of anything unless you only do highway driveing in which you may get "better" miles per gallon....

But what you are getting is an incorrect reading on your od because it thinks it's on normal size tires.

 

[pnutcar]

your speedo will be off about 5mph w/ mkiv rims

 

[IJ.]

Goon: I think he means he thought he was getting xx mpg but in reality he's actually getting xxmpg + the speedo error mpg's

 

[frontierguy25]

still don't under stand the "better" part....your not getting better of anything unless you only do highway driveing in which you may get "better" miles per gallon....

But what you are getting is an incorrect reading on your od because it thinks it's on normal size tires.

Yes that is what I'm talking about! I'm thinking that I'm only getting 300 miles on my highway trip when in fact I'm getting a little more. That's all. In the city I don't really care, but I just thought that I was driving more miles than my car was telling me, that's all I'm after.

I don't really care about gas mileage too much, my work pays for it, I just though it was odd looking at my odometer and I know that I have traveled more. If I did I would have smaller injectors and turbo.

That's all. :icon_bigg

 

[frontierguy25]

Goon: I think he means he thought he was getting xx mpg but in reality he's actually getting xxmpg + the speedo error mpg's

Exactly!!! I'm one of the last people on here who really care about true gas mileage, my foot is in the pedal more than Palin saying Mccain is a Maverick!!

Ninja Edit: More than IJ and Poodles spends on supramania!

 

[gaboonviper85]

my bad...carry on LOL