NewZed

Here's the part I remembered from the past (reading only) about how MS does advance. It's in the Mobythevan writeup about using an 83 turbo CAS/distributor. You may be setting your initial timing incorrectly, leaving no room for advance. http://forums.hybridz.org/topic/23244-megasquirtnspark-mssmsns-installation-guide/

Another thought - "Burn" isn't burning. You're putting a number in a TunerStudio box, then rotating the distributor to make it match the number in the box. You're changing the engine to match the TunerStudio numbers. But the Megasquirt ECU doesn't seem to be reading what TunerStudio should be sending it, when you click "Burn". Basically, what you're saying is that, overall, the Megasquirt ECU isn't obeying the TunerStudio commands. Could be just a communications problem between your portable PC and the MS ECU. I'd find a way to confirm back and forth communication between all components. I don't know what that confirmation would be. But it seems like your MS ECU has enough to run your engine but isn't being controlled by TunerStudio..

That's right, I am Zed Head on classiczcars.com. I'm saying that what the OP has should work. As a basic distributor. Like DIYAutotune says. He hasn't even got to "basic" yet and you have him rebuilding everything he has. Keep it simple. DIY didn't say anything about band-aids either.

Just had a thought about your jumpy timing at idle. Are you triggering on the proper edge of the holes? Maybe Megasquirt can handle the wrong edge at idle but can't use the advance curve properly. Depends on who write the code, someone might have added a feature to protect the engine if parameters aren't coming in correctly. A first-derivative algorithm might fail if the points don't fit the curve. Another odd possibility is that the knock sensor protection is kicking in and stopping advance. Still spitballing.

You can carry a turbo in the back seat and call the car a turbo car. It won't make more power though.

Moby implies that the 83 wheel will work. He did his writeup before the DIY wheel was available. http://forums.hybridz.org/topic/23244-megasquirtnspark-mssmsns-installation-guide/ You have spark so Megasquirt is seeing a crank signal and using it. I wouldn't make it more complicated than it is. Seems more like you have a software problem, Megasquirt is not doing what it's supposed to do. Megasquirt uses "prediction algorithms" to move the timing. Don't know how knowledgeable these guys are though. It's surprising how little information is out there about this. Some programs use a retard method, where you set the base trigger way advanced, like 60 degrees, others use the next cycle. Here's an interesting thread about it. http://74.124.198.224/~micro/viewtopic.php?t=17518 Here's a Hybriz response but moby doesn't really seem interested - http://forums.hybridz.org/topic/44373-predictor-algorithms/ Of course, it's not uncommon to go off on a tangent and find a problem solved without really understanding how it happened. Here's another thread showing how confusing it can get, and probably why nobody publishes anything about how the various algortihms work. Best to leave a mystery. Still might give you a new direction. http://www.msextra.com/forums/viewtopic.php?f=131&t=39578&start=0 Here's another comment (picture included, but you have six slots, not four) about using the basic evenly spaced trigger wheel, which is what you have and which seems to be working. Using a different trigger wheel should leave you with the same problem, if it's the only thing you change. In principle https://www.diyautotune.com/support/tech/other/megasquirt-ignition-control/ Anyway, the suggestions to try something else don't seem to be using the fact that your trigger wheel is triggering and the engine is running. The suggestions don't follow the facts.

Why? Factory EFI systems are designed for certain flow rates. You'd have to adjust the system back to the same performance you'd get from the stock injectors. When you're all done, no benefit.

Sequence of events when setting parameters may matter. Seems like you're taking all of the right steps. Here is DIYAutotune's recommended method - https://www.diyautotune.com/support/tech/other/base-timing/

Was I being an ass? I'm not seeing any fuel lines there. The Snipping Tool and a red line would help. How would the fuel return line be connected to the intake manifold, with a valve and some other fitting? Not getting it.

You are starting from waaaay behind. That's the coolant hose from the radiator outlet to the water pump inlet that you have your finger on in that picture. Nothing at all to do with fuel. No offense, but you need to be careful before you start messing real fuel lines. Fix the fuel fill hose problem first. It's essentially in the cabin with you so any leakage at all is raw fuel smell. Don't mess around in the engine bay until you spend some time studying. " I also found out that the lines from the fuel fill to the tank leak when slightly overfilled and I am correcting that now." Good luck.

Got curious. One of several - http://forums.hybridz.org/topic/112994-rb25-flywheel-to-l-series-question/

Here's normal sound and normal speed. Don't know who it is.

Mine sounded "cammy" when it was running rich. My neighbor thought it had a performance cam. It doesn't. Raise the idle speed, to at least spec., let it warm up and see what you think. You're off=spec. right now (low idle speed). so it's going to sound off. All engines sound about like that when the idle is too low. You've checked a lot of stuff, might as well change the idle speed to where it's supposed to be.

Idle speed is low. Not good for oil pressure or alternator charging. Beyond that you'll need to define what you mean by "off".

Same head casting number (design/style), and same head gasket?

Seems like there's a setting somewhere that isn't right. The ECU and software adjust timing by changing the coil grounding moment in relation to the base timing. So, the program just isn't controlling the coil ground like it should. The distributor is distributing and the CAS inside it must be communicating with the ECU to generate the base timing signal to create a spark. The engine runs. Could be that there's an input variable that is so far out of range that the software defaults to no advance. Maybe the MAP variable is set wrong. Maybe temperature reading? http://www.megamanual.com/ms2/ign_timing.htm Just offering ideas, and picking up some knowledge myself.

If the 78 AFM has the internal contacts for the fuel pump relay you can use it no problems. But the 76 AFM should work fine also. They're the same except some the 78's don't have the fuel pump control switch inside. You haven't mentioned fuel pressure or any of the basics that might cause a lean condition. Popping back through the intake is typical of lean.. That's why I mentioned the vacuum leaks. If the engines ran fine before, don't do anything dramatic. It's probably something simple. Might even be that the AFM isn't plugged in, it doesn't have to be to idle If it won't rev without popping, it certainly won't drive well. If you get lost, the best thing to do is download the EFI Guide and check things at the ECU connector. You can check that the AFM is properly attached, the coolant temperature sensor isn't shorted, the injectors are all connected,, etc. All from the Ecu plug.

You probably lost a lot of viewers with your title. Sounds like plug wires on in reverse rotation (easy to check), or off one hole (check timing? what is it?), or a vacuum leak. All intake air must pass through the AFM. Even the PCV system matters. The 78 should run perfectly with the 76 EFI parts. I have a 78 engine in my 76, and I've swapped ECU's, AFM's, ignition modules, and just about any other part you can think of, with no issues. I check my spare parts by using them. The 78 AFM even came with a fuel pump relay switch, just no wires in the harness for it (not your problem, just mentioning).

How much? A large number will generate more interest.

Another wild guess, or a clue for someone else - in Tunerstudio do you see the tach signal? Does it read the RPM? You said "tach" but I assume that means your in-car dash tach. I think that MS can use different sources for the tach signal. The software isn't perfected so it's highly likely that it's possible to set conflicting variables, that give results that don't make sense. Copied a paragraph from the manual as example. Maybe there's a way to set crank angle control, but still using coil output as trigger? Edit - and you're missing the crank angle signal. Only here for the puzzle. Anyone who knows the answer, feel free to crush my views.

Follow-up: Megasquirt is seeing your crank signal,and controlling the coil. The engine runs, but it's just not advancing timing. You're driving around with no timing advance at all.

I don't really have any ideas. Are you saying that no matter what the engine is doing the timing never changes. Revving the engine, watching the timing light at the damper pulley, nothing happens?

Have you been here - http://www.megamanual.com/ms2/tune.htm and looked at the section below? -

Add more detail. Like what's connected to the power transistor, MS settings, etc. Stuff that describes what you have, beyond "stock ignition system". I can say that there's not much to work with in your post, and I don't even have Megasquirt.