Early 260z Alternator Upgrade

[DRTY_S30]

Hey guys,

I'm trying to perform the internally regulated alternator upgrade for the early model 260z.  I was wondering if anyone has done this successfully and could share some knowledge on how the wiring should go?

I have read through all the guides showing the mod for the 240z and 280z but in my research I am coming across some concerns regarding the 260z.  

The guides that I have read have been helpful in understanding that I need to wire a diode to be able to shut the car off.  Guides I researched so far:

http://www.zcarcreations.com/howto/voltreg.htm  

https://forums.hybridz.org/topic/40818-260z-alternator-voltmeter-swap/

The challenges specific to the 260z are the seat belt interlock and also the fuel pump wiring.  I am still trying to understand these issues when bypass the voltage regulator.

Hoping someone could provide insight on the proper wiring here.

Thanks!

[SteveJ]

For the fuel pump, the power from the coil is tapped off the yellow wire between the alternator and voltage regulator. I suggest that if you wire a switched source for the fuel pump coil, you also include an inertia switch in the circuit to kill power in case of an accident. 

The ignition interlock unit uses the black/yellow wire coming off the voltage regulator. When the engine is stopped, it provides a ground for part of the "black box" operation of the unit. Of course, it's a challenge to find a 260Z where the seat belt interlock hasn't been bypassed. Anyway, the VR is providing a path to ground for the unit in addition to the chassis ground that goes to the unit. I'm not sure what would happen if you grounded that wire all of the time. In the FSM it is described as the Engine revolution sensor. See page BE-97. Depending upon the alternator you are using as a replacement, I could probably describe a work around.

[DRTY_S30]

Ahh okay.  I understand now.  I plan to do the upgrade to an '85 maxima alternator since it is direct bolt on and puts out 80-90A.

How do people usually handle the fuel pump wiring when doing the alternator upgrade?  Is wiring it through a switched source with inertia switch common to do for the Z's?

You are correct that the seat belt interlock has been bypassed so it is a non-issue.

I just purchased my 260z and am still learning how a car works.  I am doing a lot of studying up on the car so I can begin to "modernize" it.  I have never been a DIY car guy but I'm excited to start.  I am fairly confident in my electrical skills so I am more comfortable starting with upgrading the electrical system first ?

 

[DRTY_S30]

Can someone show me how I can tap into the ignition switch power to start the fuel pump?  Of course i will be powering the fuel pump through a relay, but I do not know where to tap into the ignition switch at?

Do I splice into the ignition wire or is there a node in the fuse box for me to tap into?

 

Edited April 27, 2019 by DRTY_S30

[w3wilkes]

You should read through tis thread, it talks about doing exactly what you're talking about. It does sound different than doing the electric pump in the early 240z's though.