Rpm rev counter to high

[Whittock1]

Hi I was wondering if you can help I have a rpm counter for my car it's reading to high is there a way of wiring a componet in line from the coil to the counter to reduce the time down to match the counter. On the back off the counter there is a switch to adjust the led display 4 6 8 these donate how many cylinders you have on your car, select the amount of cylinders ie 6 then set the switch to correspond to that. My problem is I have a 12 cylinder and the settings only go to 8 max. If I set it to 4 it reads 5000 rpm (when at idle 1000) when set to 6 it reads 4000 and when set to 8 it reads 3000. Can it be done ? I'm guessing if it had more settings ie 10 or 12 it would just keep coming down till the readings were correct. Cheers . I forgot to mention the pick up is from an alternator it puts out a 12 v signal which is switching the faster the alternator spins ie revving the quicker the signal becomes.

[Hero999]

It's possible that passing the signal through a divide by two counter and setting the numbver of cylinders to 12 will work.

[Whittock1]

Hi sounds good   but in laymans terms how do we do it ?   Remember the rev counter only goes up to 8 . Thankscforvhelping

[Whittock1]