Tach Issues... OMC 3.0L swapped for a Mercruiser 5.0L

[Sully313]

I don't see a switch on the back of my gauge to chage it to 8cyl operation. Is there another way to get my tach to work correctly with the 8cyl? Google searches mention installing a resistor inline but I haven't found information on how to do so.

The opening in the gauge cluster for the tach is a rather small rectangle so it make replacing the gauge with a different unit rather difficult.

Thanks, Sully

 

[Failproof]

Re: Tach Issues... OMC 3.0L swapped for a Mercruiser 5.0L

Look up tachs online, find the one that matches yours, then get the 8 cyl model. Or learn the math and post a cheat sheet. Other than that i would not recommend anything unless you are willing to modify dash.