Hypertech Speedometer Calibrator
12-13-2013, 12:11 AM
#1
Member
Thread Starter
Hypertech Speedometer Calibrator
Anyone have any experience with these? I recently used one on my truck. I have 295/60/20 Nitto Terra's which measure out to 34.45" per Nitto. This thing allows increments of 1/4" so I initially used 34.5". I took off in my truck and could immediately tell the speedometer was off. I checked it with the GPS and it was about 4 mph off at 70 mph and 2-3 mph off at 45 mph. Long story short, after making numerous adjustments, I finally got it set according to the GPS using the input of 33.00" and stock gears. You can change the gears also using the programer. I tried going that route but it didn't work either. Long short, it is set (according to GPS) but it doesn't have the correct tire size. Should I be concerned?
I will say I should have checked the speedo via GPS before and after I put the tires on and before using the programer.
And no I haven't talked to Hypertech yet as they were closed by the time I got around to it tonight.
Any input would be appreciated. I am not sure if I should be concerned that the correct tire input is not being used or if Nitto somehow measured their tires wrong (I highly doubt this to be the case).
I will say I should have checked the speedo via GPS before and after I put the tires on and before using the programer.
And no I haven't talked to Hypertech yet as they were closed by the time I got around to it tonight.
Any input would be appreciated. I am not sure if I should be concerned that the correct tire input is not being used or if Nitto somehow measured their tires wrong (I highly doubt this to be the case).
12-13-2013, 09:40 AM
#2
Senior Member
Draw a line of chalk on the ground and your tire. Move forward until the chalk line on your tire makes one complete revolution and is exactly even with the ground. Put another chalk line on the ground even with your tire chalk line. Measure in between the two chalk lines and see what measurement you should get. That is what you should put in your hypertech. Then check with your GPS. Your GPS might be 1 mph off as well.
Your tire height I do not believe includes the weight of your truck on them. So it is possibly that your tire compresses down to 33" with your truck weight on it.
Your tire height I do not believe includes the weight of your truck on them. So it is possibly that your tire compresses down to 33" with your truck weight on it.
12-17-2013, 04:45 PM
#4
Anyone have any experience with these? I recently used one on my truck. I have 295/60/20 Nitto Terra's which measure out to 34.45" per Nitto. This thing allows increments of 1/4" so I initially used 34.5". I took off in my truck and could immediately tell the speedometer was off. I checked it with the GPS and it was about 4 mph off at 70 mph and 2-3 mph off at 45 mph. Long story short, after making numerous adjustments, I finally got it set according to the GPS using the input of 33.00" and stock gears. You can change the gears also using the programer. I tried going that route but it didn't work either. Long short, it is set (according to GPS) but it doesn't have the correct tire size. Should I be concerned?
I will say I should have checked the speedo via GPS before and after I put the tires on and before using the programer.
And no I haven't talked to Hypertech yet as they were closed by the time I got around to it tonight.
Any input would be appreciated. I am not sure if I should be concerned that the correct tire input is not being used or if Nitto somehow measured their tires wrong (I highly doubt this to be the case).
I will say I should have checked the speedo via GPS before and after I put the tires on and before using the programer.
And no I haven't talked to Hypertech yet as they were closed by the time I got around to it tonight.
Any input would be appreciated. I am not sure if I should be concerned that the correct tire input is not being used or if Nitto somehow measured their tires wrong (I highly doubt this to be the case).
The actual tire height on the vehicle is what you are looking to program. Measure the tire from the driveway to the top of the tire. Lay something flat on top of the tire & get it to the closest 1/4". Usually a 35" tire measures around 33.5" to 34". If you are off at that point you can make adjustments.
Thanks, Gary at Hypertech