Recommendation for new radiator and elctrical fan for 280Z

[Marios280Z]

Gotcha. So you're looking for a low current source that goes hot when in ON.

 

There's lots of ways to do that, but one of the simplest would be to tap into the white/black that goes to your ignition module and your ignition coil. That wire goes hot in ON and START

Fantastic, I will use that for the thermo switch connection.

 

 

 

And this talk about fans reminds me.... If you're looking for something under the dash instead of the engine compartment, there are two curious signals up above the fuseblock that show up on the upper middlish of the wiring diagram labeled as "To Cooling Fan Motor Sub-Harness".

 

One of those wires is hot at all times and the other is hot in ON and START. You could use one or both of them to connect to your module, especially if you're locating it in the glove compartment. There was some discussion about these wires in the past in this thread:

 

http://www.classiczcars.com/topic/46256-always-hot-connection-for-radio-install/

 

 Fantastic again,  I will use the BLUE (hot in ON and START) or WHITE (hot at all time) wire to connect my manual override switch that I will also install inside the car. If understand it correctly, if I connect it to hot at all time wire, I should be able to turn on the fan even if the engine is off, do you agree? It is shown on page two of my harness install manual.

[Captain Obvious]

Excellent. And I believe your understanding of the way the system works and the wiring involved is spot on.

 

If you wire things up as shown in that manual sheet and take the override circuit green wire hot, the fan will run regardless of key position or sensor temperature.

 

Only other input I would have about the override switch thingie is that they show a 15A fuse in diagram #4 and I believe that is severe overkill. I'd be surprised if a 2A fuse wasn't big enough. I don't know exactly how much current the relay primary coil draws, but I guarantee that 15A is way  larger than required there.

[Marios280Z]

One thing that's not often mentioned with the electric fans is the extra draw on an already weak electrical system.  The 60 amp stock alternator typically can barely handle the lights on at idle.  Those fans can draw some amps.

I have been thinking about it a lot. Perhaps stupid question, but how would I know that my alternator is struggling to keep up with power demands when i have my lights on and the fans are spinning (dimmed lights? slower fan operation?engine problems due to less charge capability of the system, including undercharged battery? blown fuse?)? One of the things I have been thinking about doing to offset the power demand is to replace light bulbs with LED bulbs. All for marker lights, and rear lights. What would be left are the head lights, which frankly draw the most. But I think if I was able to find replacements for the side markers and rear that would help some.

 

Alternatively, what do we have as an option for a replacement, more powerful alternator that is drop in replacement? I hate to go this route because that sounds like an expensive rote and i have already spend more than planned on the radiator project.

 

On the other note, there is a progress. This car will race this Sunday!!

 

Did some wiring 

 

Fits nicely now. Still quite a bit room left

[Zed Head]

The dash voltmeter is a good indicator of whether or not your alternator is keeping up.  Note where it sits with everything off.  That's your base battery charge reading.  Then, after the engine is started and running at higher RPM you'll see it jump up to some high limit.  That's the alternator regulator limit.  As RPM drop toward idle speed you'll probably see the needle drop toward the normal battery charge state.  When it hits the number, that's equilibrium, power out = power in.  If it drops lower your battery is discharging.

 

The gauge isn't very precise so you'll probably just see it sitting on the everything off state.  You'll feel good when you're driving and worried when you're idling.

 

Many people have used the early 90's Maxims alternator.  It's a 90 amp output and will bolt in.  But it needs a pulley change and rewiring.  Simple in concept, but the pulley bolt needs an impact wrench and some grinding of the housing might be needed to get the pulley aligned.  I have one sitting in my garage, completed, but I've found that the small improvements here and there, relays and connection cleaning, have put my stock ZX alternator to where it can keep up, with my stock electrical parts, no fans.

 

I've also found that the cheap parts store alternators vary in their output.  The first one I used was weak.  The factory issued, old, grimy, wrecking yard ZX alternator was much better than the shiny "new" parts store reman.

[Marios280Z]

Well folks, it has happened.At autocross this morning. It was only 8pm last night when I filled the rad with coolant.Here is the final product

And here she is this morning

Still few small things left to do but I will write about it later.Time to race...

[Marios280Z]

She did well yesterday. Didn't even brake a sweat. Now I need to find a way to bring in a wire form the engine bay to inside for my manual switch. Any good that will not cause me disassemble half of the dash?

[Captain Obvious]

Awesome. I don't know much about racing... Were you in a stock class with (hopefully) similarly performing cars?

 

And as for your wire back into the interior from the engine bay, I don't have any silver bullet for that. Unless there's some function that you have stopped using such that you could repurpose an old wire for a new application, I don't have any great suggestions. Push a wire through the existing grommet?

[Marios280Z]

CO, I'm new to the aturox racing as well, so I'm not really competitive, yet. I participate to have a little bit of fun and learn fine car handling skills in a controlled environment. Because my car has some modifications done compared with stock version (springs, shocks, bigger and wider tires and brakes) I  cannot compete in a stock class and therefore I get put in a more competitive one. The 280 is not super competitive car in its class unless you really heavily modify it. For example where I am right now SCCA rules put me along side with BMW Z3 M coupe with famous S54 engine. That car easily makes twice as much horse and torque and handles better So, as I said I don't go for trophy, I go for an experience. If I want to win a trophy I sit on my race bicycle:)

 

Back to the wire, pushing through the grommet was one of the options I was thinking off. just need to find one that will lead to the cabin and I can find it without dissembling the dash. 

[Captain Obvious]

I think there are only two electrical grommets that go through the bulkhead wall. The big one on the driver's side (for the EFI) and the big one on the passenger side (for everything else). I'll take a look at the wiring diagram and see if I can come up with any bright ideas on a wire you could repurpose.

 

This is for a wire that goes hot when you hit your override switch, right? Connects to green on your control relay?

 

You done any other mods like a headlight relay upgrade?

 

 

[Marios280Z]

Yes,  It is the green wire form the relay that I wanted to hook up to a switch. The other side of the switch would have to go to a low current 12V source. I was thinking about utilizing one of the mystery  wires you have mentioned reside under the the glove box area.

 

I have not done any other electrical work yet, no head light relay. Should I? I have been thinking about upgrading the stock lights with something modern that MSA or blackdragon guys offer.  I believe at least one of the stores offers HD wiring harness that would should be put on with the new lights. But that's' a different topic

[Captain Obvious]

I was asking about mods like a headlight relay upgrade because if you would have done that mod, you would probably have an unused wire going through the grommet on the passenger side that could have been re-purposed for your fan override.

 

Independent of your fan controls though. Yes, I would recommend a headlight relay upgrade. The original switching system is overtaxed by the headlight current and I'm continually surprised they didn't use relays in the original design. They used a relay for the fricken horns, but they didn't use any for the headlights???

 

You've got a 78 right? Already has an internally regulated alternator.... Just musing ideas.

[Marios280Z]

Yup, 78 here.