distributor vs. electronic ignition

[guy_geo]

Yeah good advice, I'll try to have a quote on the parts before the car is out!!!

[H2O-Z]

Wow! This is all great stuff! This site and those on it never seem to amaze me....and I've been a Z owner for 24 years!

Ok...'nuph pats on the back for now...I got a question....

The '70 my son and I are rebuilding, is an automatic and has dual points. How does an electronic conversion vary in this?

(I know after 24 years you would think I would have all these answers....but the electrical side of auto has never been my strong point)

By the way, nowhere in this thread did anyone mention Joseph Demers distributor rebuild and conversion which I plan to implement on my own '71....here's his link...

http://www.physics.ohio-state.edu/~jrdemers/280ZX/280ZX.html

[jcdozier]

H2O-Z:

The Mallory I installed (see my 3/12 post above) is in a '71 240 with an automatic transmission. I had "disabled" the second set of points years ago (i.e., removed and tossed into the trash). Put in the Mallory (or other electronic distributor) and drive it.

BTW, if you're interesed, the Haynes manual explains the dual points. I decided they weren't necessary, (had dual points in previous cars and considered them a pain in the nether end). I drove my 240 for eight years without that second set of points before deciding to upgrade to electronic ignition.

[240znz]

I just need to add a bit here. When you turn your key to start your engine, the circuit bypasses the ballast resistor and applies 12VDC to the coil. Volts then goto your spark plugs via your points.

In additon to not buring out your coil (which I have never heard of before...thanks Daniel), the ballast resistor drops the 12VDC down to about 8 volts. While 8 volts does not provide the strongest spark, it does go a long way to saving those old points you use...and it does the trick. Just imagine how many times those little points are opening and closing very second at 3000RPM...scarey.

So, when you go to a electronic dizzy you replace the points with a solid state or magnetic sensor. So no burn out. Here's is the next benefit, get rid of that ballast resistor and you'll not only get rid of "something else to go wrong" but you'll have a really strong spark at all revs. Best of course is not having to tune it so often.

Just make sure you swap out your coil for one that can handle the extra voltage constantly.

Zed not Zee

:sleep:

[59ghia]

I just went thru my distributor, had a bad coil, and went with the petronix. So far so good. If you go this route save all the stuff you pulled and put it in a zip-lock and keep it in the car. As soon as i find another distributor (cheap) I'll set it up with points and keep it in my cubbie. Then if it (petronix) dies its just 2 10mm 's and pop in the distrib and your off and running.

[frank13]

The reason for the by pass in the ignition circuit to the coil at start up is to apply direct battery voltage to the coil to facilitate start up. Not a regulated 12V. What ever makes it from the fuse box through all the wiring to the end terminal will be what is apllied to the coil windings. Once the car ramps up and starts the key is returned to the run position redirecting the ignition feed through the ballast resistor to drop down the voltage. The reason for this is TO keep the points from buring up too soon. The points are 6 volt tech. 12+ volts would eat them up yum. I have never had a coil burn up on me. Not even bypassing directly through the B+ side of the battery. the stock coils are filled with cooling oil to combat burning them out. I would also like to upgrade my dizzy to an electronic one to rid myself of the points. If you need spare parts to carry, strip a IC module off a bone yard car next time out and throw it in the tool box.:devious:

[livenbad]

Just grazzing on the old posts and noticed this. Suggest you install a heat shield as zx distributor is very heat sensitive.

[bartman]

Hey everyone!

My 1973 240z came with a Crane electronic ignition. It seems to work fine, but the person I bought it from says now the tachometer can't be hooked up.

Motorsports says I can use the tachometer if I use the balast resistor, which I guess I'm not.

Do I need to use the stock ballast resistor to be able to use my tachometer? Will it affect my electronic ignition performance if I reconnect the ballast resistor?