Easiest way to eliminate points on 240z

[felixcatman]

On a 1973 240z with the L28 motor and SU carbs. Just want

to go electronic ignition aftermarket drop in without upsetting

the tachometer. Since the car is essentially stock, not racing,

Is there a best aftermarket drop in distributor? I'm doing a rebuild

and want to put the distributor on before dropping the motor in.

[240260280z]

Please double check but I think Pertronix make a kit that retrofits into the existing distributor housing to eliminate points.

Double check that the tach will work with this upgrade. Getting the tach to work seems to be the more difficult part.

Another popular swap is a tach from a 280zx.

Edited December 20, 2012 by Blue

[EScanlon]

Or you could just avoid all the melodrama and go for a 79 280 ZX electronic distributor with an E12-80 module. It simply replaces your stock 240 dizzy and wires in exactly like the 240, with the lone exception of powering the module.

FWIW

E

[Jarvo2]

Pertronix is the easiest! I didn't have any issues.

[Grim]

Stupid question does this car have an l28 or l24 engine just to be sure.

[felixcatman]

L28 engine

[Zed Head]

Distributors on the older engines (pre ECU-controlled timing) do more than just distribute spark. The vacuum and centrifugal advance mechanisms are built-in and curved for the engine. Something to consider. Race engine builders spend a lot of effort on their timing curves.

[EScanlon]

Don't forget that the 79 dizzy swap has been getting done to the early Z's since about... 1979 or so.

If you're building a regular use vehicle and not a race car then that swap is exactly what the Datsun/Nissan only mechanics recommend. If you're building a race vehicle, then even the Pertronix isn't the way to go.

I've done both swaps, the Pertronix CAN be problematic, but if you're careful it IS a simple bolt in and use. The 79 dizzy swap, aside from the care in replacing the actual dizzy body (to ensure timing stays true) is a true R&R project.

As a side note, the ONLY function of the distributor IS to distribute spark. The Advance mechanisms you mentioned are an INTEGRAL part of the distributor's mechanism to keep the spark at the proper point of the combustion cycle.

2¢

E

[beermanpete]

The Pertronix or an equivalent (if there is one) is likely the easiest and will work with the stock tach. The '79 distributor might be better but is not easier and it will not work with the stock tach.

[Zed Head]

As a side note, the ONLY function of the distributor IS to distribute spark. The Advance mechanisms you mentioned are an INTEGRAL part of the distributor's mechanism to keep the spark at the proper point of the combustion cycle.

2¢

E

Not really clear what you're saying there. Maybe you meant that distributor is a misnomer, or a misleading name. The "thing" called the "distributor" by most that work with it, contains the spark triggering device and the timing control mechanisms for doing that at the appropriate time based on engine conditions, along with the spark distributing hardware.

It just comes down to how far in to it you want to get. You can go simple and "slap" any old combined spark distribution, triggering and timing control device (aka distributor) in there or go a little deeper and think about the other functions. That was my intended point.

The 79 ZX probably has a decent timing curve. But the later ZX's have some radically different curves. There are ways to make things worse. No good reason not to consider it.

[esmit208]

I installed an MSD ignition and they sell the unit that allows the tachometer to continue working just fine. Any perfomance shop that sells the ignition module will usually carry the unit that allows the tach to continue to function. I also installed the kit that allows for conversion from mechanical to electronic ignition. No issues so far for almost 11 years.

[Jarvo2]

Sorry, this is the file I meant to upload earlier...shows how to simply hook up the Pertronix and have the stock 240z tach work. I followed this approach & haven't had any issues. Please note that you'll want to ensure the rest of the distributor functions as designed without much slop in the shaft.