Well, if you had one of those computer digital code readers and a laptop you can see the digital output of your rpms and you could calibrate that way.
If you have to calibrate blindly the best way is to take apart the cluster and start the car. The needles will move to their current positions.
For the gas needle, the best way is to fill it up all the way beforehand. Then with the cluster open and the car started, take off and place the needle to the full status.
For temp, wait until car has completely cooled down (overnight) then make sure in cool position when car is on.
As far as speed, when the car is started, the mph needle should move just barely, slightly above the needle stop. Recalibrate until it does. Also, when you unplug the wire harness to the cluster and plug it back it. All the needles move to max and then back down. Make sure they all move to max. Ex: MPG needle only goes 120mph instead of 140, then you know its off by 20mph. You can always pass a speed detector on the highway to find out you exact mph
RPMs are hard if you don't know your own average rpms at idle. With my current mods, mine is only around 700-900rpms. I think most people average from 800-1200.
I'm sure there is a better way to do this but this is how I did it. Not very effecient, I know but maybe someone else knows how to do it better. Hope this helps.
Sorry
Linear Mode
