The coil is very small, believe that. As of present, there is
no way to add a "Spark Injector" unit, that will provide
more spark power. You may be able to add an "After Coil" injector, like they used to make for the old muscle cars.
You can add a Tachometer, but the wire can't go on the distributor,
the car won't start if you try it. Instead, the wire can be stripped,
and inserted into the top plug from behind. You can secure
it with a small dab of RTVm or electrical tape. My tracker has a
FOUR wire plug, but only two wires used. I have the tachometoer "1/2"
stripped" lead inserted into the second slot from behind, where the NEGATIVE
lead above is shown above..