PKD

Yeah, the rad is a dual core aluminum with dual fans. I don't think its a problem. The former owner said that he made the fuel/air mixture rich because that would keep the engine temp low. Don't know if that is correct, but I think he covered all those bases with all that air flow up front, including a intercooler set up for the intake. I just got back home so I will have to check to see if there is a thermostat in there. I thought I saw a receipt from Nissan on that but I am not sure. If not I will have to see if I can get one from Nissan.

Sorting out some tunes with Chickenman. Thanks, let you know how it turns out!

Thanks Zed and Madkaw, it is a nice set up. It was built by the former owner with track racing in mind. It does really run hard and handles well. The problem has always been the tune. I have only changed a few of the lower idle settings. I haven't touched any of the other ranges(ie boost or cruise ranges). It was more to see how it reacts to the changes. The desire of this post is to get some feedback on how the Megasquirt works with our engines. There are many Miata owners with how to videos on U-tube. That's great and all but those are a completely different set up then ours. I would like to see and hear some Z info of what our cars do and react to tune variations. Who is Chickenman?

Zed, it was up to temp when we started. The turbo has one identifier on it. The reference must be a serial number, T-53218. The T is the model series as for the rest, not sure. The previous owner was building a track car to our nearby Roebling Road Raceway. We are not sure about the cam shaft, compression ratio, or thermostat.

The injectors were from the previous owner who had it built. His idea was to make this a track car. It was a nice attempt but there is a lot of things I would have done different. That said, I have never heard the term "lean misfire". Is the only remedy new injectors? Is there anything I can do with the tune to curtail. I had lowered the idle values and had succeeded in reducing the stink. My main concern is engine temp. What is the right engine temp. I am accustomed to my Fords that run with temp in the 180 to 195 range. What should the L28 be at? I had not played with anything in the higher rpm levels because I didn't detect as much smell from the exhaust, and again the turbo kicks in, which helps any fuel in the exhaust to burn fully, although I don't get any backfire or flames etc. .

Hey all, started to work on Megasquirt tuning. Currently my fuel/air ratio's are way to rich. It would take about 30sec with the garage door to earn you wings. . if you know what I mean. Stopping at a light in traffic could turn you green. My car is a 1976 Datsun 280Z. The engine is a L28 out of a 82 280ZX turbo completely rebuilt with a new turbo. The air/fuel ratio was running in the 16.5 to 18 range at idle(800rpm's) Cough Cough. What level should I be at? I have seen on some U-tube videos that they run between 10 and 13. At the same time, what temp should the engine be running at? 160? 170? 180? We tinkered with it a little, the following screenshot was where we were at when we shut it down for the day. we ended up getting the fuel ration down to 12 to 13. We bottomed it out at 10 when the temp started to go up to 185. We increased the levels and got it back up to 12 to 13 with temp at 176. following pic was screen shot of where we stopped. Also some pic's of under the hood. Some spec's: Running a MS3Pro-ECU, Delphi Fuel Injectors Low Impedance 55lb/hr at 43.5 psi. Currently running 40psi at fuel regulator, Turbonetics turbo, JE flat top pistons with a bore 3.425(86.99mm)

Will do!

Yes Patcon, I would love to start a thread. There is so many things done to this Z. I would have to find the spec sheet I received from the former owner. The engine was well built and runs well. Awesome power. Just need to get into the Megasquirt program to get the rich fuel mix to a more normal, less fume ridden mix. That car will make your eyes tear at stop lights. The former left it this way because he wanted to break it in without overheating. Since then I have added the charcoal canister back on to cut back the fumes from the tank. Why folks think removing this is a good idea, I don't know. He also disconnected the entire wiper system, I reinstalled. He took out the air system, which I have in boxes, I intend to reinstall. No heat, no vacuum line or canister to operate it. The suspension needs to be soften just a little so pot holes and speedbumps don't do damage to my spine and to the car's. Steering is wonky at best. Passenger front steering bolts came loose, had to tighten the whole rack up, needs alignment, still wobbly at highway speed. Leaking passenger door above window. And last but not least, the rear clunks like crazy! So many things can be wrong down there. Would like to convert the diff to a LSD so she isn't pegleg anymore!

I have completed my fight with the headlight gremlins! I had followed the path up down, side to side, and into several conclusions that lead to. . . basically nowhere. Checked the circuit from light switch and found everything correct. Proper voltage, on/off circuit properly working. Checked and cleaned the hi/low beam switch or better referred to as a 'dimmer switch'. As I checked the continuity of the dimmer switch with the multi-meter, I discovered the switch works fine. When attached to the under-dash wire, both hi and low circuit show return instead of hi or low. Thus a short is apparent. I checked the path with the map to discover a probable cause. Being the wiring has been disturbed for the upgrades to a more modern fuel injection system, as well as modern headlight system, relays were added. I then checked these relays to figure out if there was any disconnected or crossed wires. All functioned well. Then to the headlight loom. No problems there, other then no voltage at all. It had to be under dash, since that was where the problems began after a new speedo cable was installed. It turns out that the tachometer was rebuilt to connect to the new ecm. I had taken it apart to check as to why it would not interact with the ecm to discover the potentiometer was broken. The wiring had loose fitting. Regardless to say, the previous owner had not assembled it correctly. I went back to this and found a wire making ground contact with the dash frame that caused a short in the ground circuit that was in circuit with the dimmer switch. Lights on!

Ding ding ding, guess its getting too late for me to comprehend that the reference of "dimmer switch" had another meaning other then a rheostat. I went crazy looking at the path and seeing no correlation between the two circuits. . . duh. OK, to answer that question Zed, yes, that is where I saw the 3.5 volts that followed to the relay with the same results in voltage. This hi/low switch, does it foul(IE needing cleaning) or is it broken and requires replacement? Voltage leading to it is definately 12+volts, going to the head lights is 3.5volts. Path confirmed. Finally, any clue who would have a replacement of this switch, affordably, if not repairable??

Yep, thus the question, what could lower voltage between switch and lights. How would the dimmer effect this? Checking the resource Steve mentioned as we speak.

Nope, not much OEM in this little beastie! The previous owner wanted a track car he could drive to the track. . . pretty unsuccessful due to all what he ripped out. I am re-hooking as I go. The headlights are a little more modern so it required new relays. He took a late model box and installed it in the engine compartment. There are two relays as you supposed. The engine out of a 82 is completely rebuilt with the turbo in mind. The ecm is mega squirt, in which I am trying to interface with given it runs so rich i gag on the carbon monoxide at every light or stop sign. The drop in power on the input is definitely under dash somewhere between the switch and relay. If the voltage is dropped, would that not indicate some sort of short or reduction of voltage through bad connection?

How would I go about checking it? I did turn the knob all the way up then down, but to no effect. Does it short out the lights? Is it a wire that hooks up somewhere under the dash or to the light switch?

My 1976 280Z headlights won't turn on. We had the dash out to work out some other issues when we put it all back, the running lights work, as the turn signals, but there is no headlights. Checked the switch with multimeter and have full voltage at all wires when lights are turned on. The voltage turns off when off. No problems there. High beams don't work either. Checked voltage at high bean wire input at switch and only get 3.5 volts. Checked at Relay, the direct power is at 12+ but the input wire was also at 3.5volts for both high and lows. What did I disconnect or not reconnected properly under dash that could cause this?? They worked shortly after a drive around the block but stopped working the next time we went out for a ride!! Going nuts trying to find problem. Even changed the relays but no change. Checked under grill, pulled the connectors to left and right headlight and had no voltage at front of car. So the problem lies between the switch and the relay. Any ideas? Has this happened to anyone else that pulled the dash?? What connectors should I check?? I checked everything at the steering wheel.

Thanks all for the good suggestions. Zed's suggestion worked. It actually was in a bit better after the run around the block. I took the screw out and gave the unit a slight tap with a screwdriver in the slot and viola it went right in. I did take off the cable and check the end to make sure it was in correctly. It was but I put it back together with a little more snug. The test drive was a success. The speedo did bounce a little below 40mph then smoothed out. I don't know if that is typical for these cars? We saw no bounce or wiggle past 40 to 55. The speedo gear body might just be old. The cable is new and when I installed it to the speedometer, I ran a drill on it to see if it was working ok and it was super smooth. So my only suspect is that gear body must have a hang point in it that is detectable at slow speeds.