New Zealand Datsun Club

Yeah I have an optical dizzy. I think it was off an L20ET out a paul newman edition skyline that had rusted away, it had been sitting in a paddock for a while. I opened it up and it looked like the circuitry was covered in shellac but seemed like it was all good. It wasn't working on the bench wired up to the MS (Giving it a 12v supply as per the instructions I found online).

So I gutted the dizzy and retrofitted a sensor from a RB30 from a R31 skyline. (The wheel lines up perfectly as the original and has the same wheel config etc). But that also wasn't working so I checked my VR + Pullup settings with the manual and it seems I have it all right so Im not sure whats wrong so I feel checking it with a stimulator could reveal whatever issues I may have.

I have had it connected up to tunerstudio and had coolant sensors and stuff showing up properly, just nothing in the RPM or cam and crank logs.

I wish I was as lucky as you to get it running easy peasy I've messed something up...

Surge tank is definitely a good idea. I intend to go all out on this thing but I'm usually quite poor so I do what I can with the money I have when I have it. Hence why I bought a megasquirt, its the cheapest ecu that can do the most and be reusable in the future (hopefully).

One of the next upgrades (should cash flow permit it) Is A new fuel tank,surge tank and fuel lines. After that I want a big ass radiator and electronic water pump.
My way of thinking is that I should upgrade things that will remain in the car (or could be transferred to a new car if I had a crash, or god forbid I don't like the datto anymore.) or if I did an engine swap.

i would go for new fuel tank or a surge tank, you dont need both. If you get a new main tank just build the non surge setup into it or keep current tank and run surge tank.

Also i thought about it and you shouldn't need an oscilloscope to test the dizzy. This is presuming the RB30 guts work the same as the original guts, they do this:
The system goes from HI (12v) to LO (GND) when the optical sensor triggers. The pullup resistor to 12 volts on the TACH line keeps the line at HI(12v) until a trigger.

so all you should need is a multimeter to make sure it is grounding out on a trigger event.
also to make sure you have it wired up properly. this is the wire colors from the dizzy its self. i have no idea what the colors should be on the old efi loom side. red is 12V+, black is ground, white is trigger wire, green does nothing.

hope that helps.

One wire is for the 360 degree trigger signal, one is for the 60 degree signal. You can test both with a multimeter, but the 360 degree signal is a bit hard to watch, you need to turn the shaft very slowly.

Just for general info if using a Link computer the 60 degree signal is the "CYL" and the 360 degree is "SYNC", but you need to change the trigger wheel to one with a bigger slot for cylinder 1.

My mate sold his stimulator sorry man.

All good about the stim, but am still looking for one until I get paid and buy one lol.

Yeah I tried testing the CAS with my multimeter but wasn't having any luck so we tried an RB20DE CAS and that was also not giving us anything. We did try moving it very slowly as it should show up when the light shines through a window on the trigger. Also I think I may have rooted both of my multimeters since one has water damage and requires it to be clamped together to work and the other got a shock when I was testing something in another car and attached the battery terminals (it turned it self off and had to remove the battery to restart it :S ).

The MS3 with MS3X card has a cam input which you can run the 360 degree (1 degree) wheel sensor into and run the 60 degree wheel sensor to the crank input. There is beta code for the MS that supports this but even without that code I should still be getting a signal when wired up to the megasquirt. Since I soldered the board myself I'm thinking I may have messed something up so I figure its easier to get a stim than to look through the MS schematics and test each component individually. Regardless I did visually check every diode and resistor to see if it looked all good (which it did).


BLAH. I will get this to work. I will get this to work. I will get this to work. I will get this to work. I will get this to work. I will get this to work. I will get this to work. I will get this to work. I will get this to work. I will get this to work...