on a 1984 spider, can you do this?

[bianchi1]

i am wondering if you can disconect the motronic ignition and still have the bosch f.i. work?on the '84' cars the fuel injection ecu is sep. from the igntion..i have rebuilt a new dist ti the jim k. book, and would like to know if this is possable?

[Tifosi]

Yup, you sure can.

That's how the aftermarket ignitions work: take the motronic ICU out of the loop and replace it with something else.

The large white wire at the coil is the one that powers the ICU. Disconnect it and it'll stop functioning.

[Zunige]

As Tifosi indicated, you can absolutely do this and that is is how you change your ignition. Thus, you can have an aftermarket ignition, with your Bosch L-Jetronic fuel injection. Note that if you buy something like the RML ignition which can be found on the RML web site, and also on the IAP web site, that's how you would connect it. I'm not sure what exactly you are doing, but note that by disconnecting the Bosch Motronic ignition you are also no longer using the flywheel sensors. (Most aftermarket ignitions, if not all, don't use these sensors.)

A word of caution however. As you advance your timing, to take advantage of high lift cams, to take advantage of a better flowing head, etc. you also run the risk of "pinging". So, just take it slow, as you do these mods.

Best regards,