Tire Size/Odometer/Speedo Correction... - Page 2

Winder · 02-02-2008, 08:10 PM

Do not use the radar systems you see on the side of the road to check your speed those things are never very accurate.

My 08 Titan shows @3mph faster on the speed than it is actually going on stock tires.

If you go to a larger tire size your speed-o will be off by a %. So if the tire you put on is 10% larger then you will always be going 10% faster than what your speed-o reads. SO at 10mph you are traveling 1mph faster than what your speed-o shows and at 100mph you are traveling 10mph faster than what it shows.

There is also @ +/-3mph margin of error for the factory speed-o. Same with most GPS systems.

One of the reasons that police usually do not bother people traveling 5-10mph over the speed limit is that the margin of error of all the equipment involved falls within this range. Laser however is said to be very accurate.

ETx08Titan · 05-02-2008, 09:34 AM

I purchased the Hypertech In-Line Speedometer Calibrator from RealTruck.com for $206.99 shipped. (Use the coupon code SJ921) This was on my 08. It offeres tire/wheel size correction and gear ration correction. It was a pain in the arse to install. I had pull out the instrument panel to get the plug it connects to, but it worked. The tires I put on were wider but an 1 1/2" shorter so I was putting more miles on my truck than I was actually driving. But this fixed it and everything is reading correct according to my GPS.

Cajunguy · 05-02-2008, 09:57 AM

Handy dandy calculator for changing your tire sizes:

http://www.dakota-truck.net/tirecalc/tirecalc.html

Tilldain · 01-25-2009, 12:58 AM

i have found the best size calculator gives both the % and speed difference traveling at 60

Tire Size Calculator - tire & wheel plus sizing

TitanBlue · 01-25-2009, 12:16 PM

Anybody have a solid answer as to what Tire the Titan is calibrated to OEM? I know the XE is slightly smaller than the SE/LE Tires. I think the XE was a 31.8" or 31.6" tire. My current 265/70/17 seems dead on with GPS.

My greatest need, is to reset my Cipher for 0-60 MPH when I go to the track again. I'll change it to a 0-68 MPH or whatever, to get accurate 0-60 MPH ET with my Drag Radials. They are much smaller Diameter, about 28"

titanss · 01-25-2009, 12:49 PM

My 04 XE the speedo was set for the 265-70-18 (32.6" tall) stock tires were the 245-75-17 (31.5" tall) and the speedo was off by 3 mph. I got one of the Hypertech In-Line Speedometer Calibrator and set it for the 17's and the speedo was dead on.

tywinter · 05-26-2009, 10:10 AM

Quote:

Originally Posted by TitanTech659

Also you can use the tire pressure sensors on some but not all aftermarket wheels. It depends on the hole that the valve stem goes in.

I have seen where someone strapped the senor to the inside of a wheel instead of the stem hole. You see any reason this wouldn't work universally for all wheels?

chuyb · 07-13-2009, 10:43 PM

Hello everyone just purchased some 20" rims on 33" m/t toyo tires and my significant other says that she noticed an increase of speed down the highway today. IS HER FOOT HEAVY OR IS THIS NORMAL? 2004 se king cab 4x2