Is The 280Z Fuel Injection a "Good" System?

[TomoHawk]

I agree the stuff is pretty good, but eventually things all break down and the supply is getting thin.

In any case, I'll be giving it a really thorough tune up in the spring.

Edited January 9, 2012 by TomoHawk

[Captain Obvious]

cygnusx1, That's a great bottom line summary you posted above.

I'm beaming with confidence in my 280 now! C'mon spring!!

[FastWoman]

FastWoman... So they're IC's in those packages? Do you remember if you recognized any of the numbers? Something that you could get today in DIP form perhaps? Those flying saucer heat sinks weren't all that unusual... Back then. Heck, there might even be some germanium on that board!

All of the ICs were proprietary, never available to mere mortals, certainly not avalable to anyone now.

Hey, while you're here, what's your take on which pair of cylinders the injectors open on? Luck of the draw when you start the engine "that time" on which pair?

Exactly. When the ECU wakes up, it starts counting sparks, but it has no idea which spark goes with which cylinder.

[Captain Obvious]

All of the ICs were proprietary, never available to mere mortals, certainly not avalable to anyone now.

When the ECU wakes up, it starts counting sparks, but it has no idea which spark goes with which cylinder.

After I posted that question to you about current availability, I reread that you mentioned they were analog IC's. Unless they were some easily recognizable regulator or amp, I would consider the possibility very remote that there was a current drop in.

Thanks for confirmation about counting the spark pulses. With only a relative reference, I couldn't think of any other way it could have possibly worked, but I had to ask.

If I were designing such a system, I would hiccup every now and then on purpose, say every million pulses or so, and change which spark event I would spray on. You know... Wake up synchronized to 2&4, but after a million sprays, I would purposely drop one pulse, after which I would be synchronized to 3&6. Then after another million sprays I would drop another pulse and end up synchronized to 1&3. You would gradually roll around and end up spraying the same average number of times on each pair. Probably doesn't matter, but just to even things up. That's just me.

Of course, that kind of thing is a lot easier to do with programmable devices.

[240260280z]

Merry Christmas Bruce!!!

Finally a reverse engineered ECU schematic and test data.

Enjoy: http://www.team.net/TR8/tr8cca/wedgelab/injection/us_tr7/tr7ecu.htm

Next step: replacing AFM with MAP and retrofitting

[EuroDat]

This is a great thread. Good brainstorming.

I have a 280Z with standard engine and EFI.

I believed there was not much point in doing any mods except the temp sensor resistor mod because the ECU doesnt like it. You also have to consider the inlet manifold is very restrictive. Even going over to the turbo inlet manifold on a N/A engine doesnt help much. The runners are just too small.

This is why poeple change over to carbs. Its a simple cost versus performace upgrade.

Another common upgrade is MegaSquirt injection system.

I have seen a system with MegaSquirt II, a custom manifold, 60mm throttle body and a AFM from a toyota cressedia. It work well after fine tuning, bu it cost more than tripple webbers.

Chas

Edited January 10, 2013 by EuroDat

[Wade Nelson]

Is it a "good" system? I'd say, provided it's all working correctly, it's "good enough." Good enough to produce excellent power and decent mpg's. Relatively easy to diagnose / repair.

If you put a full modern / custom EFI on a Z, the # of hours you'd spend installing and tuning it (perhaps hundreds of hours) in NO WAY would be repaid by any additional performance you were able to squeeze out. Unless someone already DID all that work and all you had to do was duplicate it.

If you really wanted to put a bigger cam in an engine, you could potentially switch to larger flow injectors, or "cheat" the system -- for example, using sensor transposition telling the ECM the engine was cold --- to artificially enrich the mixture.

Another thing about the Z's efi is that it's an excellent EFI system to LEARN ABOUT EFI on. All the documents are here, and plenty of Z experts. You go with a Megasquirt or other aftermarket EFI you lose all of that "free" knowledge.

I'd probably look at going with a complete engine swap before I would attempt an EFI swap on the Z, unless someone I knew personally had already done it before and had the programming, maps, everything.

I'd get all the power I could from OTHER places -- headers, port & polish, compression boost, lighter flywheel, ... and leave the EFI alone.

But I'm not you.

[LeonV]

This is a great thread. Good brainstorming.

I have a 280Z with standard engine and EFI.

I believed there was not much point in doing any mods except the temp sensor resistor mod because the ECU doesnt like it. You also have to consider the inlet manifold is very restrictive. Even going over to the turbo inlet manifold on a N/A engine doesnt help much. The runners are just too small.

This is why poeple change over to carbs. Its a simple cost versus performace upgrade.

Another common upgrade is MegaSquirt injection system.

I have seen a system with MegaSquirt II, a custom manifold, 60mm throttle body and a AFM from a toyota cressedia. It work well after fine tuning, bu it cost more than tripple webbers.

Chas

The stock intake manifold on EFI Zs isn't as restrictive as you think. First get rid of the restriction in the head, then it might be worth it to look at the intake.

Is it a "good" system? I'd say, provided it's all working correctly, it's "good enough." Good enough to produce excellent power and decent mpg's. Relatively easy to diagnose / repair.

If you put a full modern / custom EFI on a Z, the # of hours you'd spend installing and tuning it (perhaps hundreds of hours) in NO WAY would be repaid by any additional performance you were able to squeeze out. Unless someone already DID all that work and all you had to do was duplicate it.

If you really wanted to put a bigger cam in an engine, you could potentially switch to larger flow injectors, or "cheat" the system -- for example, using sensor transposition telling the ECM the engine was cold --- to artificially enrich the mixture.

Another thing about the Z's efi is that it's an excellent EFI system to LEARN ABOUT EFI on. All the documents are here, and plenty of Z experts. You go with a Megasquirt or other aftermarket EFI you lose all of that "free" knowledge.

I'd probably look at going with a complete engine swap before I would attempt an EFI swap on the Z, unless someone I knew personally had already done it before and had the programming, maps, everything.

I'd get all the power I could from OTHER places -- headers, port & polish, compression boost, lighter flywheel, ... and leave the EFI alone.

But I'm not you.

Simply trying to cheat the system by upping pressure or changing fuel injectors when putting in a bigger cam won't work, at least not well. The fueling curve will be much different.

Headers won't give you much of anything on a stock engine, performance increase from compression without changing anything else are also minimal as well as limited, port and polish won't do much either without supporting modifications. A lightweight flywheel, on the other hand, is a great upgrade!

It's not as easy as it sounds. Basically, if you want to keep stock EFI, it's not worth it to heavily modify the engine. If you plan on serious modifications (e.g. headwork, cam, etc.) then either triples or standalone EFI give you performance and ease of tuneability. There are other ways of improving performance without doing engine work, besides giving it a good tune-up and making it run as good as it can, including closer-ratio trans, lower geared diff, lightweight flywheel, big exhaust (keep stock manifold).

[rcb280z]

The stock EFI is a good STOCK EFI system. As long as it works correctly. Had contemplated removing my stock efi a couple years ago. But with the help of this forum and the FSM I made some, a lot actually, repairs and she runs as she did new. Like a stock system should. Good performance and fuel economy as far as I'm concerned. Easy to work on, now. And I'm smog legal here in CA. So I now like the stock EFI.

[Wade Nelson]

Seems like you're then one without a clue...

I"m only going to say this once before it devolves into a flame fest.

ONE OF YOU IS WRONG!

[Captain Obvious]

Finally a reverse engineered ECU schematic and test data.

Haha! This has been bugging you since we talked last, hasn't it? :classic:

You are a fountain of information. If it's not already on your had disk, you seem to be able to dredge it up from somewhere.

I can tell already that the schematic is very different in spots than the 280Z ECU, but I bet the basic concept is very similar. That's awesome! Merry Christmas to me! I am going to have fun with that!

[TomoHawk]

and a AFM from a toyota cressedia.

Why this unit? Did it have a bigger throat or less flow resistance? It looks similar to the 280Z unit.

At least it is for the larger 3L engine.

Edited January 11, 2013 by TomoHawk