Timing did that much for you? I'm up at 7200 ft and if thats all it takes to be able to run 35's I guess I'm out of excuses.
what is your MPG
- Thread starter beardedforlife
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Common Core math - we are writing about it and not explaining anything nor is it very relevant. Common Core for sure.
'94, 240,000 miles, 285/75 MT's, speedo correction gear, roof rack, lots of armor, fridge, etc.
I average 10-11 around town, 12-13 freeway w/o the trailer. Towing the trailer 9-10. No complaints. It is what it is.
I average 10-11 around town, 12-13 freeway w/o the trailer. Towing the trailer 9-10. No complaints. It is what it is.
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thank you for that link. I was under the impression that I just didnt have a fuel light.
Would a larger diameter tire affect the miles counter by showing fewer mile driven for the same distance compared to the factory size tire?
I think this would also affect the MPG accuracy.
It does affect the speed, so I would imagine the mileage would also be off.
I think this would also affect the MPG accuracy.
It does affect the speed, so I would imagine the mileage would also be off.
you bet
Use this site to calculate the percent difference and than apply it to your mileage http://www.onlineconversion.com/bigger_tires.htm
going from stock 31 to 35 is a 12% change on the speedo using the site's calculator. Add 12% to the odometer
Use this site to calculate the percent difference and than apply it to your mileage http://www.onlineconversion.com/bigger_tires.htm
going from stock 31 to 35 is a 12% change on the speedo using the site's calculator. Add 12% to the odometer
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With a larger diameter tire you have lower revs per mile. I think that translates into less miles clocked for the same distance traveled, but at a higher speed on the speedo.
So the MPG calculated on cars with larger than OEM tires would erroneous, since there are more actual miles traveled than shown on the odometer. Therefore the mpg would actually be higher (more real miles traveled for the same amount of gasoline used).
So the MPG calculated on cars with larger than OEM tires would erroneous, since there are more actual miles traveled than shown on the odometer. Therefore the mpg would actually be higher (more real miles traveled for the same amount of gasoline used).
Crazy question: What if my speedo is off by approx 7 mph? I'm running 31x10.50 BFG AT KOs. I have been running this size and brand tire for 15 years or so. Would this affect my mileage as well? Or is it just a speedo cable issue. Just curious. Haven't bothered with it because, well, I can add and it keeps me from worrying about getting a speeding ticket because I'm 3FE powered! 
I think the answer is above your post. I hope I'm right.
96LX, 315/75R16s, roof rack with my spare on top of it for extra wind resistance, ARB winch, gear and stuff and everything I refuse to throw away because I'm lazy, and I am too public schooled to do the common core math and calculate the 12% difference for the rubber overdrive, ODO is getting a solid 10 MPG in town.
So, if your speedo is reading 7 mph FASTER than you're going, you won't have to worry about a ticket, but you will be registering more miles than you're actually traveling, thus, you are getting WORSE gas mileage than you calculate and you are racking up miles on your rig faster than you really are. Typically, speedo's are off by percentages rather than a fixed number. The faster you go, the more number of MPH you are off. With my 33's they are approximately 5% larger than stock. At 10 mph speedo I will actually be traveling 10.5 MPH. At 50 mph speedo I will actually be traveling 52.5 MPH. At 70 MPH speedo I will actually be traveling 73.5 MPH.Crazy question: What if my speedo is off by approx 7 mph? I'm running 31x10.50 BFG AT KOs. I have been running this size and brand tire for 15 years or so. Would this affect my mileage as well? Or is it just a speedo cable issue. Just curious. Haven't bothered with it because, well, I can add and it keeps me from worrying about getting a speeding ticket because I'm 3FE powered!
Yes, my actual difference is 6.4% but 5 is easier to calculate.
This works the opposite way if you are running smaller tires.
Then start calculating gear ratio changes and a good set of Donks, then you can really be cool!!!
Speedo isn't calculated at being off 7 mph-only at a certain speed. It's off a percentage. All the calculators for tires are based on it being correct in the first ans a presumed tire size. Start over from scratch to see exaxtly how it reads-I don't overly trust gps-etc. Drive 100 miles along mile markers.
You all say this but I have the same issue on my 93. Before I went to 35's the speedo was reading 5mph faster from 20-75mph. It wasn't progressive which is what I would have expected, I thought maybe the speedo gear jumped a tooth or something.
Now with 35's on it reads 5mph fast around 20-30 then progressively gets on target, by the time I hit 75 its reading dead on.
Use odometer. ignore speed. it isnt necessarily same. Figure exact error. Use calculator on phone for multiplier while tank fills then divide gallons in easy once exact multiplier based on odo error if figured
No it's not. My numbers take a GPS-validated correction factor into account.
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How can one do it without the use of GPS?