I have seen many tach's that run off of an injector line, and then i have seen some that run off of a probe strapped to the alternator, I dont have expirence with eather type,,,
The one for the alt is a autometer, and the injection line, well all those seem to be a digital read out, And i done really want one of them,,
Is anyone here running one of the two types mentioned here???
Please, any imput would be appreciated!
Peter.

 

I have an alternator tach; works like a charm. (It also double as an electric-intererence detector when the engine is off and it picks up the blinker pulses...)

 

Begle1,,, How does it know the engine rpm? dont alternators spin at different speeds on different applications??? Auto meter, says it is a install and play, No adjustments, I just dont see how with different automakers spinning the alt at different speeds,,,per engine rpm..
Am i missing something?
Peter

 

I have the AutoMeter alt. tach. You have to calibrate it to engine RPM. I don't know where it says that particular tach is "plug & play", obviously that is bad info.

If you know somebody with an optical tach, you can calibrate it that way. Or just run your tire size and gear ratio through one of the many online calculators and calibrate it on the road.

 

Where might i find one of these online caculators?? I have a small hand held gps to get my speed just right, speedo bounces just a bit.
Thank you,,,
Peter.

 

This is the first one that popped up on a Google search. There are a zillion of them.

http://www.et-studios.com/motorsports/gears/gears.html