Speedometer calibration
Junior Member
Joined: May 2025
Posts: 27
Likes: 7
From: West Coast between the desert and the mountains
If the information I have is correct the limit to how high you can increase it would be to 2532. You can try 2550, but it may not work. There might be no change or it will revert to your factory value in the PCM. Either way you will not wreck anything.
Looking where we started - tire circumference 2463 with speedo at 60, GPS at 63-64
last change - tire circumference 2500 (increase of 37mm) with speedo at 60, GPS at 62
If you change tire circumference to 2532 (increasing another 32mm) with speedo at 60 you should get a GPS reading of 60.5-61. I would try 2550 and if it doesn't work then put in 2532 and you should be really close.
Let us know.
Looking where we started - tire circumference 2463 with speedo at 60, GPS at 63-64
last change - tire circumference 2500 (increase of 37mm) with speedo at 60, GPS at 62
If you change tire circumference to 2532 (increasing another 32mm) with speedo at 60 you should get a GPS reading of 60.5-61. I would try 2550 and if it doesn't work then put in 2532 and you should be really close.
Let us know.