Z31T ecu swap now complete!
 

Wahoo!!! I finished the Z31T ecu swap into my 280ZXT today. Holy sheet it made one hell of a difference!!! I decided to do this as my Z would lean out REALLY bad at mid to full throttle. I'm sure it was the stupid AFM, but I'm sick of the flap door. Now I'm runnin MAF! I got it running today & went for a drive. At 10psi, the tires wouldn't stay planted above 5k rpm through the first 3 gears. My dyno last year @ 10psi was 220whp, and this feels MUCH MUCH better than last year. AND... I got my manual vent controls back in! YAY! :D

Now... gotta get it to pass emissions & then it will be dyno / track time!

sweet. And that MAF really helps to clean things up.

No doubt man, great job bro'! Man I wish I could afford a Turbo swap right now. Keep us up on your smog, and dyno/track results. Sounds like it is going to be real sweet.

Looks awesome.. It almost makes me wish I had installed the Z31 setup I had before I sold it. And man does your engine compartment look clean!

hey nismo, would that swap work for a na application, or am i better off to do the megasquirt route? im tired of my unadjustable flapper door 1975 technology too.

are the MAFs between the Turbo Z31 and N/A Z31 the same? Cus I have a spare Z31 N/A MAF lying around.

would this work with N/A 280's?? also, would the injectors off that same car flow more and still be a direct replacement??

Ummm.....WHAT? Ok, now I am confused. The Z31T is a V6....the 280zx is an inline 6...two totally different ECU's, one is a speed density the other a MAF...why are you doing this to me??? lol I know a MAF set up is superior to the speed density but can you tell me how you got THAT to work? I read on a site that you could use a cobra MAF on the L28ET and I thought...nah you cant do that! Please feed this quest for knowlege. By the way, it looks kick ass!!

if i know my z's the z31 was also batch fire, so as long as you hooked up all the sensors the right way the only real thing thats changing is your going from an AFM to a MAF, on a stock setup..

Batch fire? So they are all fireing at the same time?

You're coming up to Layton to take me for a drive, right?

:D

the injectors anyway, it fires them in batches, for example......
1&3
2&6
4&5

instead of a direct fire, wich fallows the firing order.

Ahh, I see. That makes more sense for me...what was I thinkin?

another thing is, could this be used in N/A 280's

this is gonna keep me up all night to.....

Looks great i def. want to see some dyno results.

Hoov i just noticed your comment.
i think it would, and it would be a huge improvement over the AFM we have now.:unibrow: :038:

Alright homies... guess I shoulda stayed up all night :D



I've never seen anyone do this on the N/A. The reason it's so easy on the turbo is because the 280zxt & all Z31's use the same ecu plugs. You just have to cut & solder several wires. You will need the entire Z31 n/a ecu wiring & run it to all the sensors, or at least cut the Z31 ecu plugs & solder them onto the 280zx n/a ecu harness.


Yep... all Z31 MAF's are the same. But the MAF is not compatible w/ the 280zx ecu


Hoov cleared most of that up. The COBRA MAF is used with the Jim Wolf 400hp ecu.

There are several changes that must be done to do the Z31T ecu swap.
#1: VG30 distributor chopper wheel (optical crank angle sensor disc) must be used in place of the 280zxt one. It has a larger hole at TDC for better timing & fuel control.
#2: The fuel pump is controlled differently, so the fuel pump & relay must be grounded differently.
#3: the Z31 ecu controls a couple sensors using diff wires, so they must be cut & solders to the correct wires.


Yes I is! Where you been? You need to post more in RacingUtah.com!



So anyway... it was an easy process since I had the 280zxt & z31t wiring diagrams in front of me. All in all, it cost me $30 and about 6 hours.

To do a Z31 n/a ecu swap, you'd just need both wiring diagrams & understand how each ecu receives & sends info to the various sensors.

Here's where I got all my info:

The Z31 ecu swap guide:
http://forums.hybridz.org/showthread.php?t=91250

Another similar guide (less helpful for me, but talks about diff ecu options):
http://www.freewebs.com/1971datsun24...0Injection.htm

And Lifegrddude's SAFC thread:
https://www.zdriver.com/forums/240z-280zxt-s30-s130-tech-tips-275/z31-setup-w-safc-17290/

That would be bloody sweet if you guys can do the "Z31 n/a ecu swap" !!!

nice. You did that in six hours? It took me that long just to lay the stock turbo wiring harness in my car. :D hehe...

I just hope I can get my car running soon.

anyone know were I can get a cheap afm for a spare? I want a backup for when my afm craps out again. I saw some on line for like $240, but I don't want to spend that much. All I need is one that works right and I can put it in a box, and let it sit untill its time comes to be used.
also I was doing some thinking today about the cold air intake I put on my z, and I was wundering if anyone has ditched the crome tube, and boot, and just put the filter on the afm?
when I snap throtle right now there is a split secound hesitation with the cold air intake on, do to loss of vacume. I havent noticed any bad isues with it, but I figured that ment that I am not geting as quick respons as I was geting befor. I am defenatly getting more respons, just not in that split secound. is there somthing that you guys with the system do to avoid this vacume loss? and don't say yea I put a turbo on.

Well... I did spend about 3 hours going over the wiring diagrams & making a spread sheet for diagram comparisons.... So I had it all planned before I started.


Turbos have lag anyway... :D If you need a spare AFM, check www.ebay.com or your local junk yard.

Oh... one other thing I thought of for the n/a ecu swap.... you'll need an 82-83 280zx turbo distributor, because you need an optical CAS.

Yeah they can go out without warning. I have already been through the AFM nightmare, and it is one piece of equipment on the car, you can't skimp on. I got the one on my Z from e-bay a while back, and it ran me $20 plus shipping. Just keep checking back on there periodically, and one will show up again. Usually a lot of newer listings take place on Sunday evening, good luck to you. Oh I just thought of a place you can get a used one for $75 or so.www.zxman.com, check his site out. I will check it here in a bit.

Yeah I just checked his site, and they are $74.95 plus shipping. Also he lives in Texas, so maybe he isn't too far from you

so no one has stuck the cone filter directly on the afm? I think I am going to find a way to make room and do it. the only thing is that wouldn't that kind of blow the afm out of wack? I mean it is an air density thing right, and if it is coming through a restriction that close to a vain, how could it get an acurate reading?

Hey nismopick did u write down all the stuff u needed and a step by step " how to " u know what i meen if u did can u post it ? or send me it.. i have a huge alot of z cars i can find and get partz off of.. 240z 260z 280z 280zx's turbos 300z-31's and z32's there is a place in " Amarillo Texas called " ALL ABOUT JAPANESE " auto recking they have every single z car i could dream off i went there this weekened .