My dad is sending me a tach he had on another truck. He said I will have to put two little magnets on the harmonic balancer. Any comments on this setup? Pros and cons?

 

Just make sure they clear the crank sensor! If they are small you should be able to put them forward of the crank sensor. Other than that, no problems I can think of. Hard to turn down a free tach.

 

My truck came with an isspro tach with the crank trigger setup. With only two triggers (magnets) the tach is not exactly in 'real time', but it works very well for steady cruising. The gauge is huge , prolly out of a big rig catalog, and is mounted just to the left of the glove box where the vent would be on the not-so-poor-boy model There's an isspro pyro/boost combo mounted above it that is equally huge. The holes were already drilled in the dash when I got the truck, so I worked with what I had

 

If any of you 1st gen guys want a cheap, accurate, easy to install tach try one of these http://www.tinytach.com/tinytach/diesel.php

It measures rpm off a transducer clamped to an injection line.

 

I don't like digital tachs for the same reason I don't like digital speedometers. If they don't update quickly enough it's hard to see what the rpm is when the engine is revving quickly. I have a GPS which includes a digital speedometer which updates once per second. Even though it gives speed in 1/10 mph increments, it's hard to get your speed set with the Cruise Control. Imagine trying to get your shift points when the tach only updates once per second.

Edwin