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

[Captain Obvious]

That TR-7 ECU is probably a couple generations newer than the one we have. I haven't seen any schematics for our ECU's, but I suspect there are sections that would be very similar despite the newer design. Not all of it, but sections maybe.

However, I can attest that those similarities do not extend to the output stage. A while ago I drew up a schematic for the output stage of our ECU, and ours is very different than the TR-7.

[TomoHawk]

The TR7 ECU is supposed to be the "L-Jet" type, and the external connections are what we are familiar with, so it looks like the oxygen sensor was just spliced in to modify the mixture.

[EuroDat]

What is the advantage of going the TR-7 ECU route? It must be more than just an oxygen sensor. Does it have other possabilities like easier to tune etc?

[TomoHawk]

With all that we do know about the system, all we need is a basic schematic, and one of our engineers could easily build a PIC based ECU with a number of adjustments (or even a "boost" button) to fit into the old ECU box. It would even be half the size.

[TomoHawk]

The TR7 ECU with the oxygen sensor just looks like an attempt to incorporate an oxygen sensor to be slightly more auto-adjusting as to the mixture instead of just the (pre-programmed settings) that the L28 engine uses.

[Captain Obvious]

What is the advantage of going the TR-7 ECU route? It must be more than just an oxygen sensor. Does it have other possabilities like easier to tune etc?

I think there's a misunderstanding here... Nobody has suggested swapping a TR-7 ECU into the Z. The only reason we're even looking at it is because Blue turned up a schematic for the thing. I wouldn't try to get it to work in the Z, I was just interested in knowing more about what's inside the ECU and because they're both Bosch L-Jet systems, there are probably some similarities.

With all that we do know about the system, all we need is a basic schematic, and one of our engineers could easily build a PIC based ECU with a number of adjustments (or even a "boost" button) to fit into the old ECU box. It would even be half the size.

Heh. Hasn't that pretty much been done already? They call that Megasquirt? Different form factor, but that's what you got, right?

Well, I've got a schematic for our output section. You do the input section, and we'll trade, OK? Then we need other people to do some of the intermediate blocks, and we're done!

(And I've already got a "Boost" button. I'll post about it sometime when I get energetic.)

Edited January 17, 2013 by Captain Obvious

[TomoHawk]

Megasquirt is a digital type of EFI, using a different set of sensors and such.

[Captain Obvious]

Megasquirt is a digital type of EFI, using a different set of sensors and such.

Right. Sorry, I thought that was what you meant.

If you're looking to reuse all the original inputs and outputs, then you don't need a schematic. All you need to know is how the ECU functions as a black box. You need fuel, temperature, and time maps. All you need to know is WHAT the box does, you don't need to know HOW it does it. For that, you don't need a schematic.

Your PIC programmers could care less what's really inside the original box. They just want to know how the output should react to the inputs, right? A schematic won't tell you that.

[EuroDat]

Hey Tomohawk,

Are you going to take some kind of performance test before you change the AFM?

Its pretty crude, but I do a simple test by going full throttle from 60 to 140km/hr in 5th gear and timing it. Taking notes at 80, 100, 120 and graphing it in Excel. Doesnt say how much hp your producing, but it gives you an idea if your improving or wasting your time.

Chas

[TomoHawk]

I can measure that kind of performance using my Android tablet and a performance application.

For the ECU, I would personally like to have it work like the analog design,to keep it in the spirit of the original designs, although a simple microprocessor would probably help to make up for certain things. An oxygen sensor and MAF sensor could be used to add better control of fuel delivery, for better low-speed efficiency and top-end power, though I would not even try to duplicate contemporary performance. Even an altitude "switch" could be included for high altitude (1500m?) use. Any "tuning" would be done with your little screwdriver, by adjusting some mini-resistors mounted on the circuit board.

[EuroDat]

I can measure that kind of performance using my Android tablet and a performance application.

Aah the wonders of modern technology.:bulb: Ill have to remember that when I start playing with mine. Im having trouble with injector 3 and 4. Looks like I up for a new set.

[TomoHawk]

I'm just wondering that if you wanted to build an ECU from the TR7 schematic, what would it cost to build it, and install it in the 280Z ECU box, assuming that it would work? You'd have to re-engineer the small parts that include the integrated circuits, because they are proprietary and most likely no longer exist,which would probably be the onlytough part.