Can anyone inform me about the fuel injection systems on the 260 and 280 Z cars?

Really only two questions.

1) Do they act independently of the ignition system?

2)or Do they depend on an electrical trigger signal from the distributor?

123Ignitions will work with mechanical injection systems,,, so inquiring minds would like to know.

Thanks in advance

Ed

Hey Ed, glad to hear you're still thinking Z cars and expanding the applications.

The 74-78 Z's with FI all use a single wire from the coil "-" terminal to the ECU pin 1 as the ignition trigger, so technically as long as the coil output is "the same", then using an 123 dizzy shouldn't cause an issue. Practice may differ from threory as usual, but I'll bet it will be okay.

To expand a little on the above... The fuel injection system does not act independently of the ignition system, and yes, it depends on an electrical trigger signal from the ignition system. However that electrical trigger does not come directly from the distributor, but in fact comes from the output side of the stock ignition module which (just like points would do) pulls one side of the coil primary to ground through an open collector transistor.

The fuel injector controller squirts fuel on every third ignition pulse that it sees.

So... Unless you're dramatically changing the dwell so much that it confuses the fuel injection controller, or doing something like multiple spark discharges that might be counted duplicate by the injection controller, then it probably wouldn't matter.

I'm worried that I'm not explaining myself well here... Does any of that make sense? :bulb:

Thanks that helps a lot

The 123 ignition's electronic ignition module should look the same to the tach and ECU as the factory electronic ignition module, and the commonly used GM HEI module replacement, or even Mallory Unilite, I would think.