Purchased a 72 race car that had been using the original Z wiring.  I am in the process of rewiring by removing all original wires and replacing with new.  My only elec. components are elec. fan behind the radiator, gauges, rear lights, fuel pump, ignition, cool suit and the original defrost/heater blower.  So far three questions:

1. There is a single wire attached to the center of the brake pressure differential located just below the front brake booster.  Is this needed?

2. I believe the car still has the original alternator.  One wire from a elec. post labeled "E", one wire from a post labeled "A" and a T plug with two wires.  Is all I need to do is attach the "E" wire to a ground, "A" wire to the positive post on the starter and the T plug disregard?  Should I replace the alternator with an upgrade?

3. Do I need the voltage regulator?

Thanks for any help.

 

 

 

You don't need the wire on the brake splitter. I'm not sure about the alternator wiring. But depending what alternator you may or may not need a voltage regulator. I race ITS and use the stock alternator, voltage regulator and wiring. Where are you located? Any pics of the car?

Chuck

 

I'm not sure about the wire it might be a pressure sensor. If you want to ditch the old alternator with regulator go to qualitypower and buy a GM 1 wire alternator. Choose the 1" lower mount and cut off your lower alternator bracket a little. I had the 110amp model and fits perfectly. If you don't have a lot of electronic components to worry about they had a race special mini alternator that will for sure save some weight and space.


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Chuck,

Thanks for the quick response.  From other photos I'm sure it is an original alternator and with removing all the original wiring I will need to investigate how to rewire the regulator in if I need it.  I guess an alternative would be to replace with an alternator with an internal volt reg.

l'm located in Wisconsin and plan to run both IT and vintage.  Have a second '72 with an '82 turbo.

Looks nice! Better check the IT rules on the alternator and voltage regulator before you change them. If they don't specifically say that you can then you can't. Mine works fine as-is and there's always been something more important to mess with so I haven't looked into the alt/e-reg. BTW, I also have a 72 with an 83 turbo engine/trans. :-)

Chuck

 

If the rules allow it, i say change it and put the GM one. If you keep the original, you need to connect the T connector. The GM 1 wire is easy to connect, 1 battery cable, terminal #1 gets ignition 12V and Terminal #2 gets the voltage sensing wire. If not follow the schematic since its an external voltage regulator. Again, if the rules allow, use an internally regulated alternator.

I checked the GCR. Looks like you have to stay with the stock alternator and voltage regulator.

The only mention of alternator for IT is - "n. Alternate water pump, alternator, power steering, and crankshaft pulleys of any diameter or material may be used. Type of accessory drive (e.g., V-belt, toothed belt, etc.) shall remain as stock."

Chuck

 

Chuck,

Midwestern Council's GCR says the same thing but when it states an alternate may be used doesn't the now allow for an undated one wire GM alternator with an internal VR?  With the current 40 year alternator installed might be best to change it before the season and also not having to worry about hooking up the old VR correctly.

 

13 hours ago, Mojos 72z said:

Chuck,

Midwestern Council's GCR says the same thing but when it states an alternate may be used doesn't the now allow for an undated one wire GM alternator with an internal VR?  With the current 40 year alternator installed might be best to change it before the season and also not having to worry about hooking up the old VR correctly.

 

Can you post the rule that states an alternate may be used? My quote above applies only to the pulleys. I found nothing in the GRC talking specifically about the alt/e-reg. You can use a replacement 240Z alternator but it has to be similar in size and weight. You can't swap  in some new lightweight alternator. Same thing goes for a battery. If you're running at the front you better keep everything legal. But if you're not then I doubt if anyone will care.

Chuck

 

I am misreading the GCR sentence, that just the pulley for the crankshaft can be changed and also the alternator pulley.  I see that I would need to stay with the current stock model.  Thanks for pointing that out.