Adding Triple Webers to the 240. What else do I need?

[5 Star Rising]

Upgrading the 71 Series 1 240Z to triple DCOE 40 Italian Webers. My car is pretty much stock. What is a must as far as parts/mods needed to run this set up? I'm new to these carbs and the set I have is used and I dont know their history other than they look to be in good shape from the outside lol. Came with a Cannon Intake.  Will I need a mandatory electric fuel pump, pump relays, oil pressure switches, fuel pressure regulator?

 

I read some posts here but everyone had a different car, some with pusher electric pumps at tank ect. Would like to keep it as clean and stock looking as possible as far as added wiring, switches and all that.  Also I read somewhere that there is different ways to route the fuel to your carbs. Would love some advice on this upgrade. Hope to have this build done in a few months after a long 5 year restoration.

 

Thanks in advance..

[bpilati]

 You need the electric fuel pump and regulator, linkage and fuel rail. Check your fuel tank for rudt.

[5 Star Rising]

Do you know if a series 1 car has a fuel pump wire in the rear harness?

[AydinZ71]

49 minutes ago, 5 Star Rising said:

Do you know if a series 1 car has a fuel pump wire in the rear harness?

no. 240z’s utilized a mechanical pump. You will need to install a relay. The trigger signal for the relay needs to come from the “on” signs of your harness. Check the amperage of your fuel pump so you can match it to the relay rating. 
 

There are 2 types of fuel pumps for cars: high pressure for EFI (30-60psi), and low pressure for carbs (0-5psi). You want the latter. 

[5 Star Rising]

Right, I have been looking at the high capacity pumps 70 gph but 3-7psi. Someone had mentioned there is a blue taped up wire in the 240z harness in the rear that was not used. I was curious if that was on a series 1 car also, or just the latter cars. I know the 73 240z uses a "pusher" electric pump in the rear in conjunction with the mechanical pump up front so that one definitely has the wire in the rear.

Edited March 19, 2021 by 5 Star Rising

[AydinZ71]

11 minutes ago, 5 Star Rising said:

Right, I have been looking at the high capacity pumps 70 gph but 3-7psi. Someone had mentioned there is a blue taped up wire in the 240z harness in the rear that was not used. I was curious if that was on a series 1 car also, or just the latter cars. I know the 73 240z uses a "pusher" electric pump in the rear in conjunction with the mechanical pump up front so that one definitely has the wire in the rear.

ahhh if the 73 had a pump near the tank, then I was just unaware. I still think you should run a new relay and wire since you don’t know what that amperage that wire was originally designed for. You could try, but you may heat up the wire or burn out the terminal/switch. 
 

I found the wiring diagrams from Haynes to be pretty accurate, so you could use that as a reference. Might give you the color of the conductor, and which wires it will be traveling with. 

Edited March 19, 2021 by AydinZ71

[NewZed]

Here's the 71 wiring diagram from the Owners' Manual.  It's a green wire with a 20 amp fuse.  Finding it and using it is discussed off and on over the years on various forums.

 

[AydinZ71]

Wow, that can handle a pump up to 240w. Maybe you don’t need a relay! Check the specs on the pump you are looking at. Clearly @NewZed is much more helpful fuel than I am LOL 😂 

[LooseRocks]

That green wire is pretty big.  I would say it's probably at least 12AWG.  Most modern pumps are pretty low current relative to their capabilities.  A largish Aeromotive pump (SS Fuel Pump) is drawing <15A flowing 140GPH.

[madkaw]

Doing a upgrade on a 72 . I would recommend what was said earlier , run a relay . I would get a T for your oil pressure sender and add a pressure switch and use it as the ground for the relay . I would pull power from the battery directly for the relay . I would run the pump 12v from the relay and tie into the green wire under the glove box . I don’t know whether I would use the ground back at the tank or just ground the pump at the chassis at the pump - probably the latter . 
I would order a fuel pump meant for an older carb engine like a Mazda rx7 . Summit carries a Carter that puts out 2.5lbs of pressure - perfect for triples and no regulator needed - 50$. 
Wouldn’t hurt to put a inertia switch in line with the pump for safety 

[LooseRocks]

In my '71, there's a ground wire in that part of the harness that's screwed into the chassis.  I think it was meant to be used in conjunction with the green wire if you add an electric fuel pump.

[5 Star Rising]

I'm looking into fuel pumps and wiring, also off the topic of electrical but also for the addition of the triples, what do you guys do with this pipe? Plug it or add a breather?

[jonbill]

catch can with a breather.