What are the actual differences between all model '81-83 turbo ECU's?

[Guest bastaad525]

I know I see them categorized in different ways, usually by:

 

- year

- auto or manual

- federal or CA emissions

 

And I'm just wondering what kind of differences there are between the different versions.

 

For instance, how do the fuel curves differ? How about the ignition curves? Is it known that a certain model(s) performs better than another?

 

Would anyone be able to tell me which is best for my setup? Stock turbo motor with Nissan 5-spd, 13-14psi of boost, RRFPR for extra fuel pressure. I'm not 100% positive but I think I have an '82 CA Auto ECU, I think the donor car was originally auto, since it came with a Nissan 5-spd instead of the BW. But I dont really know.

 

If it's worth even looking at changing I'll check it out, I can probably trade for a different model for free, a friend of mine usually has a few laying around.

[SleeperZ]

The '81 supposely didn't have a fuel cut-off at high rpm. It should plug right into the distributor, even though it had a CPS on the crank pulley, but don't quote me on that since the crank turns at twice the speed of the dizzy. I don't know of any real differences between the rest of them.

 

I prefer the '86 turbo ECU as the later turbo units use an expensive O2 sensor, and the non-turbo units aren't curved for boost. The earlier turbo ones may work ok too. It's a much nicer conversion, I think you'd like getting away from the crappy flapper.

[Guest bastaad525]

yeah make no mistake I'd like to go with a 300zx ecu or even MS at some point and that may actually be happening soon if I can get my hands on an '82-83 dizzy, but in the meantime was just wondering about other 280zxt ECU's. As I mentioned, I have a friend who deals in used Z parts, he often has several ECU's on hand. He'd likely just trade with me for free if I asked him to switch for a different year or model of ECU. So if there could be some performance gained there it'd be worth finding out.

[dragoontwo]

why not just get MS, and use it with the '81 dizzy?

[Guest bastaad525]

thought about that as well. MS is still pretty pricey, I know the common consensus is that they are very cheap, and relative to any other standalone they are, but I'm lazy and no good with electronics, so I'm looking at buying the pre-assembled kit, with preassembled wiring harness, and a few other bits that push the whole setup well over $500 for me. Still a great deal no doubt about it, and I am still VERY interested in doing this at some point.

 

About setting it up the way Tony D did to work with the '81 CAS, modifying the crank pulley and such, that looks like a pain in the ***, and I think it'd go MUCH easier if I just find a later dizzy.

 

In the meantime, I may be getting my hands on a 300zx ECU and MAF soon at an AMAZINGLY good price , so that will probably be my next upgrade, and I"ll definatley need the later distributor for that, whether I go MS in the future or not.

[Tony D]

The stock CAS is only about 10 degrees shy of a simple "crank it and go" installation like the 82/83 setup.

Someone just has to take the time to pull the CAS off and figure out how much they have to grind from the bracket to allow that adjustment, and it will be far simpler than I did it.

But you will be limited to 40 or so total advance degrees. Just as a forewarning!

 

You don't have to pull the pulley, but it was the only way I could think to do it with a engineered exactitude. I knew the slots were X degrees apart, and pulling the pulley didn't seem like abig job to me.

 

If pulling the pulley seems like a big job to you, you need to SERIOUSLY reconsider ANY modification to the fuel system beyond the stock setup. ANY of the modifications you propose take FAR more than a simple drop swap n go kind of retrofit! They will all take effort.

 

Wether you want it on the front end in following directions and preparation, or the back end in aggravation and items detonating to oblivion, there WILL be aggravation and effort involved. I guess the big question for any system you install will ultimately be:

How FLEXIBLE will it be to suit your needs now, but MORE IMPORTANTLY: In the FUTURE?

Can you move it to any other vehicle you buy if an accident happens?

How well has it worked with other people's setups, and do they have proof or simply subjective commentary?

Is the cost for the system front ended or backended. That is, once you get teh ECU, how much time/money is blown getting it to FIT?

[Guest bastaad525]

If pulling the pulley seems like a big job to you' date=' you need to SERIOUSLY reconsider ANY modification to the fuel system beyond the stock setup. ANY of the modifications you propose take FAR more than a simple drop swap n go kind of retrofit! They will all take effort.

 

Wether you want it on the front end in following directions and preparation, or the back end in aggravation and items detonating to oblivion, there WILL be aggravation and effort involved. I guess the big question for any system you install will ultimately be:

How FLEXIBLE will it be to suit your needs now, but MORE IMPORTANTLY: In the FUTURE?

Can you move it to any other vehicle you buy if an accident happens?

How well has it worked with other people's setups, and do they have proof or simply subjective commentary?

Is the cost for the system front ended or backended. That is, once you get teh ECU, how much time/money is blown getting it to FIT?[/quote']

 

and THAT is exactly why I have not gotten myself an MS yet! Too many questions, too many jobs with possibility of endless complications. This car has never ceased in throwing curveballs my way... the other day, a simple brake caliper and pad swap, what should have been a 1-2 hour job tops, turned into like an 8 hour job, because of stupid unforseen complications. I would NEVER have thought of the problems that popped up. So when I look at the stuff you guys are doing to get MS in and running (a bit more to it than a simple caliper swap) all I see is the endless potential for problems that I can't even imagine.

 

That's why when it came time to get SOME sort of fuel solution to allow me to run a bit more boost than 10psi, I 'chickened out' and went with the RRFPR, it was the option that seemed to have the least possibility of problems, and even THAT didn't go off without a hitch as the metal return line broke and one of the rubber fuel lines kept leaking. I can only imagine if I had decided to go with bigger injectors... much as I would have prefered to go that route....

 

But I'm still imminently interested in doing either the Z31 swap or MS, I want more performance, and I think this is the best way to get there w/o spending a fortune. Eventually i'll either work up the courage to try it myself or I'll make friends with someone local to me that has the time and knowhow to lend a hand. Until then I'll keep asking questions and gathering info... can never know too much.

 

 

But back to the original question.... Anyone else know if there is some performance to be gained by going with a different year/etc. 280zxt ECU?

[lifegrddude]

As far as I know the ecus are the same. Didn't the 83 have more initial timing though? I looked on the hood of an 83zxt and it read 24* btdc and mine is 20*. I think that's about the only diff.

[lifegrddude]

Btw, if you are ever in SD and need help with the Z31 swap, I'll be glad to help you out. I'm just returning the favor since I got so much help from Afshin and the others when I did the swap.

[Guest bastaad525]

hmmm I could swear I've heard there are differences between the ECU's... timing curve differences or something, to compensate mostly for the differences between running a manual or auto trans.

 

 

lifegrdude - have you done or are you familiar with the swap then?? I could bring the car down to SD I suppose, I go down there ever so often to vacation anyways.

[lifegrddude]

Bastaad, yep I did the swap about 6 weeks ago. The wiring only took about 2 hours to do, but I had to troubleshoot some gremlins before I had it up and running perfectly. I don't know how much of a difference there will be for the swap, since if I remember correctly you're using an 81 harness, but it can't be too bad!

[Guest bastaad525]

actually everything on my setup is '82 except for the CAS. Kind of a long story how that came about, but anyways the wiring harness is '82.

 

Right now I"m just trying to locate a good '83 dizzy and the z31 chopper wheel. I'm trying NOT to pay a fortune but at the same time I'm really not up for using junkyard parts. I've had too much bad luck as it is.

[Tony D]

Bastaad, I got to apologize!

ianz just left the house with a freshly-killed 81 ZXT motor we pulled from an 8/81 production date ZXT, and like an IDIOT I did not take the time while I had an engine out and sitting on the ground to dissect that bracket to find out about the alterations to the bracket. Now he has TWO sitting at his house... I got to go over there and look at that damnable bracket and figure this all out!

I do have the ECU here at the house, though, and internally the 81 is different from the later units. I believe this is due to the injector grounding circuitry in the ECU, as well as some ground plane modifications.

[Guest bastaad525]

hey no rush man, I won't be doing MS next week or anything

[SleeperZ]

The Z31s are a dime a dozen in the Denver area yards. I can extract the wheels without having to pay for the whole distributor. I can't imagine you'd have an issue using this part used....I'll let you know when I've got one.

 

While everyone is thinking about the differences in S130 ECUs, what about the Z31 ECUs, specifically manual versus automatic for the turbo units? I now have an '86 Federal turbo ECU for an auto, and an '86 Federal turbo ECU for a manual...I may just switch to the manual ECU, but the automatic one has worked very well for a while now.

[cygnusx1]

Bastaad, I never got any straight answers about the ECU/Year/Auto/Manual differences either. I would imagine that a company like Jim Wolf might be able to answer your questions. A factory manual from each of the years might also shed light but would be difficult to pull off...unless a few people on here have the manuals and scanners...wink-wink. I have tried "supposed" automatic and manual ECU in my hybrid and see no difference. I am not sure of the year/model they are. I even got ripped off on ebay with a fried ECU. I now have three of them total; one is dead.

[Tony D]

Muahahaha!

 

"I would imagine that a company like Jim Wolf might be able to answer your questions. "

 

Yeah, they could the even BIGGER question is wether they would!

 

Bernard and JeffP have been collaborating, and have a pretty good grasp on some of the differences, you may want to post the Z31 question to them directly. They are not so secretive as JWT... LOL

[Bernardd]

 

While everyone is thinking about the differences in S130 ECUs' date=' what about the Z31 ECUs, specifically manual versus automatic for the turbo units? I now have an '86 Federal turbo ECU for an auto, and an '86 Federal turbo ECU for a manual...[/quote']

 

main differences are the fuel recovery values and a bit of timing. they are fully interchangeable IMO.

[Guest bastaad525]

main differences are the fuel recovery values and a bit of timing. they are fully interchangeable IMO.

 

 

EXACTLY! See those are the differneces I am thinking about. While they don't keep all the various flavors of ECU's from being compatible, they could provide a significant differnece in driveabililty. Maybe the fuel curve or timing curves are very different between a manual or an auto transmission car? Maybe not?

 

 

Sleeper... haven't been to my local wrecking yard lately, but just in general I've noted that Z's are few and far between there. If you get your hands on a good Z31 distributor and want to send it my way for a good price definately let me know. I should be getting the Z31 ECU and MAF within the next week or two.

[SleeperZ]

Will do. And yes, I'd be very interested in finding out those specific small differences in the fuel and timing...I'm just not into digital electronics like I used to.