Haltech wiring ignition basic questions

[Blitzed]

Hello,

Have a few basic questions about installation of Haltech Elite 750, 73 240Z NA. Overlaying the Haltech wiring harness to the existing 240Z harness, can't get my head around some of the connections.

First ignition wire (Key switched 12V) Which wire on the 73 240Z ignition switch is the switched 12v (on) ? (B.Y., B.W, W.R, L.R, or G.W) I have a FSM but not an expert on wiring diagrams. 

• Terminate the existing  ignition wire in the connector and replace with the ECU ignition wire or splice into the existing wire  and leave it in the connector?

The configuration is not typical and information is limited at best. Running a single HEI coil to a hall effect (reference and sync single) sequential distributor (cap and rotor, plug wires to SP). No coil pack (waste) or COP set-up. See coil pic. 

 

Second coil and resistor question. If I look at the 73 240Z wiring diagram (from ignition switch)

B.W, and G, W connect to the resistor. Correct? Do these wires connect to any other components?

B,W from the positive side of the coil connects to the tach,  Correct? any other components ?

The black wire on the negative side of the coil terminal, does this wire connect to or drive any other component in the existing harness? 

My concern is wiring the new coil directly to the ECU harness and terminating the wires from the (ignition switch, coil and resistor) will this termination impact other components in the existing harness?

Any help would be appreciated. 

 

 

 

[Zed Head]

The diagrams never show the colors from the device, only the colors in the main harness.  So you'll have to use the plug to convert from device harness to main harness.  

I screwed up and used the 74 260Z diagram.  Deleted those pictures.  Steve is on the proper car.  Oops.

Edited June 30, 2021 by Zed Head

[Zed Head]

Deleted some wrongness.

I would just use the R, B, S, and IG to decide what to use to power your Haltech and parts.

Believe Steve.  That would be a great political slogan...

 

Edited June 30, 2021 by Zed Head

[SteveJ]

In the START position, the G/W wire goes through the tachometer and comes out B/W. The B/W wire goes to the positive on the coil.

In the ON position, the B/W wire goes to the ballast resistor and comes out G/W. The G/W wire goes through the tachometer and comes out B/W (different B/W wire than at the switch). The B/W wire goes to the positive on the coil.

The B/W wire from the ignition switch (ON position) branches off to a few different functions. The most important one is going to the fuse box. Downstream of the 20A fuse it powers the turn signals, tachometer, brake warning light, and switched source for the alternator/voltage regulator. (Note: for some of these circuits, the wire is Green, but it came from the same source.) Before the fuse box, there is also a branch off the B/W wire that is Green. It goes through an inline fuse and comes out Green. That is for the electric fuel pump. It might have been re-routed for the Nissan modification that actually installed an electric fuel pump in the North American 240Zs. (Long story...) The B/W wire also provides power for a couple of emissions related circuits, but I'm guessing you or a previous owner have defeated and/or removed most of that.

For the 240Z, the black wire off the coil is grounded by the points when they collapse.

[SteveJ]

36 minutes ago, Zed Head said:

Deleted some wrongness.

I would just use the R, B, S, and IG to decide what to use to power your Haltech and parts.

Believe Steve.  That would be a great political slogan...

 

Meh. Even I don't believe much of what I say. 😉

 

[Patcon]

Isnt that what makes a politician!

[Blitzed]

Thanks Zed Head and Steve J,

Still a little confused but getting closer to really confused, how I like it. 

Ign switch: 

Based on the response I should spice into (and not remove) the switched 12v ign wire from the Z harness. Too much going on down the path. The Haltech wiring harness has a fuse box and the ECU ign wire will be covered by this circuit. 

Coil and resistor wires:

Not concerned with the existing tach wires, will try the ECU/tach conversion provided by Duffy using the existing stock 240z tach internals

. 

Splitting the white wires and running white/red through the ECU and white black to coil +. Sounds the solution to the old Z tach internal. 

Still concerned with what to do with the coil wires / connections. The HEI coil has a external suppressor (see pic), single pin connector. Does a coil suppressor function the same as a ballast resistor? 

Thank again, 

[SteveJ]

Did the Haltech come with wiring instructions? If so, post them. It's hard to guess what you are trying to do. It would probably be easier for me to draw it up correctly for you. For the right price, I could even make a junction harness for you to plug in between the dash harness and ignition switch. Why hack into the wiring if you don't need to? 

The drawing you posted on the Pertronix has a flaw that could lead to hard starting. Having a couple of diodes in the right place would give the Pertronix the correct voltage when the car is starting without trying to power the ignition circuit.

[Blitzed]

Hi SteveJ,

It came with a wiring diagram for the new components. The more I talk this through or over thinking it. There are really only two connections from the stock harness. ECU to the IGN switched 12v (key) and connect the black/white on the positive side of the old coil to the positive wire on the HEI coil, should be good. There are no points so the negative (black wire on old coil) side of the coil is eliminated. The ECU will ground the igniter and coil. 

All other connection remain the same. New new coil requires an igniter wired through the ECU and connects to coil, the new distributor wires directly through the ECU (no connection to the coil other than the coil plug wire to distributor cap).

All other sensor have assigned wires through the ECU. 

Will just keep the stock ballast resistor and connections in place. Not sure if they're needed or function but it can't hurt? I guess :)

 

 

[SteveJ]

If the voltage is too low, yes, you can hurt some electronics. 

[Zed Head]

45 minutes ago, Blitzed said:

HEI coil,

Will just keep the stock ballast resistor and connections in place. Not sure if they're needed or function but it can't hurt? I guess 🙂

Not really clear how Haltech does their ignition.  Might want to dig in to that a little more.

https://www.haltech.com/wp-admin/admin-ajax.php?action=ht_get_file&id=5d227b76506c252c8b7fb0d1&op=1

https://www.haltech.com/wp-admin/admin-ajax.php?action=ht_get_file&id=5d351552506c25377c49fae6&op=1

[Blitzed]

Hi All,

Correct, ignition module required. The HEI coil pic in this post has a 3 pin igniter/ ING module (blue dot on top) integrated. All of this is straight forward, wires coming from the ECU and neg from coil. 

My concern is eliminating a connection from the existing harness at the coil and ballast resistor. 

Thanks,