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Sure, but please keep the reference to my website

I've set up a new project which contains a full replacement of the existing board. It is as simple to build as my previous conversion but is based on standard components and does not require an attiny programmer or programming software anymore. The old project is now deprecated, the new one can be found at the same link: http://www.dinoplex.org/tachoconversion/ Enjoy, Adrian

The Bosch red coil/ballast resistor (0 221 119 030) works well as a replacement for the factory coil, it has the same primary resistance and will even give a bit more output.

This indicates a problem with the fuel supply, your carbs are running empty and then the engine dies. Check the fuel lines and filters and clean accordingly, if there is rust and gunk in the filters then your fuel tank will need a good cleaning too. Then check the fuel pressure at the fuel line feeding the carbs, your workshop manual will list the correct pressure for your carb setup (probably somewhere between 2.5-3.5 psi). Also make sure that the Napa pump is the correct size and delivers enough fuel and pressure.

Speaking of coil packs :-) Looks not really out of place as the spark wires are coming from the same location.

If you get a spark then i would expect that your pickup is ok. This sounds rather like mixed up spark wires or a too advanced or retarded ignition timing. Check your spark plug wiring to really make sure you didnt mix up one or two cylinders. If in doubt, start the engine and let it idle, now plug one spark plug at a time (don't get zapped) and listen to the engine, does it run a bit smoother? Then the spark plug in question was wired to the wrong cylinder. If it does not change, the corresponding wire or plug might be broken. Also check the ignition advance with a timing light (vacuum disconnected), is the advance correct at idle? This would indicate a too retarded ignition timing.

That leaves the Ignitor, which seems to have gone bad, or the magnetic shim had a bit of play and started to vibrate at high speeds but i guessed you checked that already. I don't think its a problem with the supply wiring as your points setup is ok and the Ignitor is merely an electronic version of the mechanical switch, so your wiring seems to be fine.

Sounds like the supply power wiring if its not temperature related, but then the symptoms would be the same when changing to a points ignition setup, as the supply wiring itself does not change. The symptoms you mentioned could indicate a defect Pertronix coil. If there is a broken wire or short in the secondary (output) winding of the coil, the output voltage would be quite low and barely sufficient to create a spark, especially at higher RPM. You could run the factory coil and resistor with the Pertronix ignitor as a test, the combination is equal to a 3.2 Ohm coil.

This might be a problem with the Ignitor overheating, i had similar effects with an Ignitor installation where the engine would start to run rough above 5000 RPM, then gradually it got worse until i let the engine cool down, and everything would be fine until the engine heated up again. Did you notice the same issues with a cold engine? The overheating issue seems to be a design fault with the Ignitor. The Pertronix Ignitor uses an IGBT transistor for driving the coil, which lowers the coil current for circuit protection when the temperature rises considerably. Up to 150ºC internal temperature everything works nice, then the current drops progressively up to 175ºC where the available current is below 1A. The round mounting plate of the Ignitor is the heat sink of the IGBT, but as the engine (and thus the mounting plate) easily heats up to 80-90ºC, the IGBT can't cool down and warms up even further, up to a point where the coil current is so low the ignition starts to cut out. You could either use a points or Pertronix Ignitor setup to drive an external (robust) transistor ignition, as example a MSD 5900 or convert to an optical pickup and transistor ignition such as the Crane XR700. Good luck, Adrian

They look a tad melty indeed. These are DCOE 45 carbs? Webcon lists part number 69602.450 for the venturis: http://www.webcon.co.uk/weber/45dcoe.htm#17 Here are two shops who offer the venturis as a spare part for $24-$25 each: http://www.carburetion.com/weber/weberventuri.asp http://www.piercemanifolds.com/product_p/69602.450.htm

The current driven Z tach has a small coil below the wire loop to pick up the current spike, the spike is then amplified by a two stage germanium transistor (2SB189) circuit to drive the indicator needle coil. If you build a small circuit to convert the 200-400 Volt kickback pulse from the coil (-) terminal via a resistor feeding into a 5V zener diode and then trigger a standard BC547B transistor to put out 500 mV to the tach's pickup coil black wire, then you are all set I would add a schmitt trigger after the transistor to clean up the signal, but thats just me. Here is a small project i did to convert my current driven tach to interface with an electronic ignition (MegaJolt), which might help building a kickback triggered conversion: http://www.dinoplex.org/tachoconversion/index.html Best, Adrian

Condenser is the old technical term which is still used in the automotive area, but Walter is correct, the correct term is capacitor. Just don't try to order a capacitor at a parts store, they wouldnt now what you need Best, Adrian

I would recommend borrowing or purchasing a new battery first, the symptoms you have described could result from powering the car with the charger only. Can you post some photos of the ignition module and magnetic trigger, that would help with the identification of the parts Sorry, i don't know the 260Z wiring well enough to answer your question regarding the ground strap, but adding one is certainly a good idea.

The tacho just shows the ignition impulses received by the coil, those impulses also create the 'angry noises' which you normally won't hear because a running engine is louder than the coil. Question is why the coil receives ignition impulses at all. My wiring scheme for the '74 260Z indicates a point breaker setup, do you have a points setup or an ignition module/magnetic pickup fitted? If you have a points setup, check out your contacts and the capacitor, the contacts might be touching each other and create a partial connection due to the high current flowing, a defective condenser could have similar effects (simple test, what happens if you disconnect the condenser?) With an ignition module either the magnetic sensor/pickup is broken, or the ignition module is defective. Disconnect the pickup wire from the ignition module, do you still have the erratic ignition impulses? If so, the ignition module is most probably defective, otherwise the magnetic pickup might be the source of the problem. Did you encounter the problem with a fully charged battery or with the charger still connected? An electronic charger connected to a dead battery can create similar symptoms when you put a load (ignition circuit) on the circuit.

This would point to the contacts not doing their job. You may want to remove the distributor cap and give them a visual inspection to check if they are correctly in place and clean, check also the wire going to the outside screw terminal. If you need to clean the contacts/points, use brake cleaner or gasoline and a swab, but don't use sandpaper or anything abrasive. Now connect the test light to the distributor wire and +12V again. If the contacts are currently closed, open them and close them again, does the light now stay on/blink? If the contacts are currently opened, bridge them by (gently) introducing a screwdriver blade inbetween the points, the light should go on then. Good approach. You might ignore the condenser for now until the light tests indicate that the contacts are ok. If you get +12V to coil (+) both on starting and ignition on, your contacts switch coil (-) to ground and the capacitor and coil are good, then you should get a spark. You might also want to check you distributor cap and rotor as well as the spark wires and plugs, but that can wait until you get a spark from the coil. good luck, Adrian