Standard setup on 240/260Z is that current goes through a resistor to the tacho then to the coil. Therefore a resistor type coil is required.
Has anyone removed the resistor and run a non-resistor coil and still retained the tacho? I am not game to put full 12 volts throught the tacho in case i stuff it.

Personally, I wouldn't risk a relatively hard to replace and expensive item like an original Z tacho.

Why do you not want to run a ballast resistor ?

Cheers,

_________________
Chris [;-{)>

Only that both my brother's 240Z and my 260Z don't have R type coils so will have to buy a couple. I am told that the spark out put from a non-resistor coil is lower than from a Resistor coil if using a resistor.

In other words, with a resistor the voltage is dropped to about 8 volts and a 12volt coil then produces less spark.

No big deal and I agree it is not worth rtisking the tacho.

It's a bit of a fallacy that non-resistor coils produce more spark. A coil with a resistor runs cooler and lasts longer.

If you want a better spark, the coil needs to be saturated longer. Normally this isn't possible as the contact points have a limited range of dwell angle adjustment. But by using either an electronic ignition kit to fix the dwell angle across the range or by using a 280ZX distributor to do the same thing, you'll get a coil which operates at it's optimum saturation level producing a consistent spark regardless of engine revs. Which is good.

Cheers,

_________________
Chris [;-{)>