Here are gearing charts for the FJ with lists of sprocket sizes and tire sizes.
http://www.fjowners.com/index.php?topic=669.0Having just completed the installation of a set of Speed Hut gauges. The GPS speedometer and stepper motor driven tachometer together read spot on when compared to the above mentioned charts.
I have no personal knowledge of the Dyna ignition system or how it is set up. I will mention that during the installation of the Speed Hut tachometer, there are directions that tells you how to set the tachometer to read the correct engine ignition pulses. The gauge is pre-set to indicate 4000 rpm in the pulse menu. For the tachometer to read the correct rpm's, the gauge needs to run through the pulse setting procedure and be set at 1000 rpm's.
I know this has nothing to do with your Dyna ignition, but I wanted to point out that the Dyna ignition is a universal item just like the Speed Hut tachometer. The FJ engine is a wasted spark engine. You may want to try setting the Dyna to read as if the engine is a 2 cylinder.
Fred