SteveJ

Yes, sir.

I experienced the rub when I went with bigger wheels, though I'm not sure you will like my solution. The lower valence was pretty beat up on my car, so I swapped out to an air dam. The air dam did not have the clearance issues that I had with the stock valence.

Think of the headlight as two resistors. They are both connected to the battery positive. Since the Normally Closed contact on the second relay is connected to ground, you can see the green and blue connect. That means the low beam circuit has a path to ground until that coil could energize. However, even with the switch in the high beam position, the coil can not energize. So electrically, when you move the high/low beam switch to high beam, this is what the circuit looks like: While the coil in the relay is an inductor, for the purposes of this explanation, we will only look at the resistance (impedance) of the coil. At the headlight, there are two branches to the circuit. One goes through the headlight high beam filament and the relay coil and returns to negative. The other branch goes through the low beam filament and returns to negative. Since we know the voltage of the battery (12 VDC) and the resistance of the components of the circuit (4 ohms for the filament and 80 ohms for the coil), we can calculate the current flowing through each branch and the voltage drop across each component. Total current = Battery voltage divided by Effective resistance R1 = R(headlight) + R(coil) = 4 + 80 = 84 R2 = R(headlight) = 4 Since this site has limited HTML capabilities, here's a link to see how to calculate effective resistance: https://www.electronics-tutorials.ws/resistor/res_4.html R (eff) = 3.82 ohms Total Current = 3.14 A Indeed, when you apply Ohms Law to each branch of the circuit, it matches our results. I1 = V/R1 = 12/84 = 0.14 A I2 = V/R2 = 12/4 = 3.00 A So now we can calculate the voltage drop across each component for the branch with the high beam coil. V (high beam filament) = 0.14 * 4 = 0.57 V V (coil) = 11.43 V Even if that is enough power for the coil to pull in the contacts, you have another problem. When the relay contacts connect the high beam circuit to ground, the voltage at the coil drops to zero. (In the first diagram, the black wire would have 0 VDC to ground with the relay contact closed. It is all the same wire electrically speaking.) When the coil de-energizes due to no voltage, the contacts will return to their normally closed state. Your headlights would switch to low beam. The coil would energize and swap to high beam. The voltage at the coil drops to zero...ad infinitum until you swap the high/low beam switch back to low beam.

The short answer is that it won't work. The longer answer is that you will never have sufficient current flowing through the second relay coil. You have a parallel path to ground. I've made a simplified drawing of your circuit that I hope allows you to see the issue. If you removed the high/low beam switch from the car and had the headlight switch on, you would find you have 12VDC to ground on both the red/black wire and red/white wire. The headlight would not be shining, and the filament just acts like an ordinary piece of wire. In your drawing, you have the low beam circuit on a normally closed contact. That gives it a straight path to ground. This actually renders your other design flaw moot. The second flaw is that the headlight and second relay coil are in series. The relay coil has a resistance of around 80 ohms. The high beam filament has a resistance of less than 4 ohms. Since they are in series, that means the voltage drop across the coil is going to be at least 20 times more than the voltage drop across the headlight filament. At less than 5% of its designed operating voltage, the headlight would not even have a dim glow. All working examples of headlight relays isolate the positive and negative for the relay coils from the positive and negative for the headlights. Also, it's smarter to have two positive wires and one negative wire for the headlights in case you ever want to use LED headlights.

The downside is that my wife has already reported me to HR...twice.

To elaborate on what @Patconsaid, if you don't have the coil wire firmly seated against the contact in the distributor cap, you WILL have arcing between the wire and cap. This arcing will heat up a destroy the center post on the cap. I actually got a $700 discount on my 260Z because of this. The owner planned on selling it for $3200 but knocked it down to $2500 because it wouldn't run. With a new cap and new plugs, it ran fine. He still sold it to me for $2500.

Pop a huge bowl of popcorn for this one. The audio isn't great, but the subject of the interview is.

He's in Madison, WI.

I'm glad it worked to your satisfaction, Ron. From the first of my research, I read that the LED color should match the lens color. I might have used some white LEDs in the center gauge pod, though. It's been long enough ago that I can't remember. The bottom line is that you will be able to see at night. I suggest that you replace the 20A fuse in the parking light circuit with a 10A fuse. The wiring wasn't really up to handling 20A, so if you get a short, you could melt wiring (or a connector) with the 20A fuse.

If you retard the timing too much, the engine won't run. You can run the car with the static timing at 30 degrees. It will ping like crazy if you aren't running racing gas...So I've heard from a friend.

While the tach is out, you could use a meter like this one to test the signal going to the tach. https://www.amazon.com/gp/product/B0002LZU7K or https://www.amazon.com/Mrcartool-Digital-Multimeter-500-10000-Temperature/dp/B07VKLKDZL Connect the positive lead to the blue wire and connect the negative to ground. Put the meter on 6 cyl and start the car. If the signal isn't consistent, then you have a different issue to track down. If the signal is good, your tach is going bad.

I just happened to remember the thread.

If the Speedhut gauge sensor is 1/8 NPT https://www.amazon.com/GlowShift-Female-Sensor-Adapter-Reducer/dp/B00NWZZBS6 or https://www.amazon.com/Fitting-Female-Metric-M16X1-5-Adapter/dp/B07GRT81L7 If the Speedhut gauge sensor is 1/4 NPT https://www.amazon.com/Fitting-Female-Metric-M16X1-5-Adapter/dp/B07HGVF2PY or https://www.amazon.com/Fitting-Metric-M16X1-5-Female-Adapter/dp/B07DJZKQHY

I believe it's the same as the 240Z.

He had several opportunities to practice his recoveries over the weekend.

Let's go for a ride.

Here's a quick video. My nephew was filming this at the last Mitty. Watch for the Alfa that's a few cars behind John Morton. I was closer to the turn and caught the same action from a different vantage point with my camera.

From the ZCON 2018 Judged Car Show: By the way, this video is available in 4K. If you can, watch it that way.

Actually it was 1999. That was the 4 cylinder Z concept. Nissan actually conducted a survey of Z club members back then. I did not give it a rave review. While I could tolerate the front (barely), the rear styling is horrid to me.

It looks familiar... I guess there's not too much that can be done with that shape.

I just put the rheostat on the lowest resistance, and I leave it there.

Are you referring to LED or incandescent bulbs for 5W draw from an 1156 bulb? Phillips lists the incandescent at 26.9W. The wattage of the different types of incandescent bulbs are listed in the spreadsheet I attached to the post in the other thread. There is not a ready replacement for the rheostat. The bulbs I used aren't overwhelmingly bright, so I have no need to dim them. If you replace the turn signal bulbs, you will need to replace BOTH flashers. I have been using these for 5 years: https://www.amazon.com/gp/product/B011BTMDQM There is one on the driver side under the dash, and the other is on the passenger side.

The fuse is a current limiting device by definition. One of the problems with that circuit was that it was designed to have too close to 10A draw, so the engineers selected a 20A fuse to prevent nuisance trips. This gives the opportunity to build up more heat at the fuse clips. At close to 20A, that sucker will glow in the dark. I have seen it. Using the 10A fuse in conjunction with the other steps I listed will reduce the opportunity for heat to build up to the point of melting the fuse box. If the fuse is blowing at that point in time, it could mean it's time to clean the corrosion from the fuse box and light sockets again. For owners of 73 and later cars, there is another incentive to drop the fuse to 10A (after swapping over to LEDs). The gauge of the wire at the 9-pin connector on the combo switch is too small to support 20A of current. I had a short at one of the bulbs in the gauge light portion of the parking light circuit. Since the current in the short was too much for the wire, the 9-pin connector was damaged. A properly sized fuse (in this case 10A) would protect the wiring and connnectors.

You could try this bulb. It appears to have a low profile to fit under the green lenses. https://www.amazon.com/Grandview-Chipsets-Vehicle-Bright-Courtesy/dp/B01C2SHTZ6