ECU and O2 Sensor Type

I'm not absolutely sure about this but I believe that you are stuck with the hardware - like, if an 87NA ECU is your base and you want everything to work more or less out of the box, you have to use a titania sensor AND a tune meant for it, so, like, you might want to start tuning off, say, an 85T image. I've actually experimented with this a lot, my Nistune is in an 87NA ECU. The 87T and 88T stock tunes included in the base ROM pack do not seem to get correct O2 readings and start and idle much better with it unplugged, 84 and 85T tunes run far better with it plugged in. That said, out of the box the stock 88T tune is still miles better than anything else even if I leave the O2 sensor unplugged and have a shitty cold idle and cruise a little rich.

Not a Nistune expert at all yet but it doesn't look to me like you could tune it for the "wrong" 02 readings like you're asking. But I could be wrong about this.

I picked up an 84 Turbo, and it's an automatic. I am planning ahead for the transmission swap and tuning. There's an 87 Turbo ECU available right now, and finding a good 87-89 M/T Federal ECU hasn't been easy (rusty or overpriced) to say the least. What I was trying to figure out is if I could have Jim Wolf Tune the ECU, or use NISTUNE to tune it myself without having to switch 02 sensor bung and type from Zirconium to Titania. But from what you're telling me, and from what others have said, the correct way to go seems to be getting an 87-89 NA ECU and tuning that even if they are hard to find.

An automatic ECU will run a 5spd car just fine, so you don't NEED to change that before you do your tranny swap.

Regarding Nistune, the vendor I dealt with would only do a Nistune install on an 87+ ECU. I don't know why, and I hadn't heard that before. If whoever you have do the Nistune install doesn't care about the year of the ECU, then you don't even need to find a new one.

Yes, I know. I could keep the 84 A/T ECU that's already in the car. I don't have to get a used 87 NA ECU now. Maybe I will never have to.

I am not sure why the vendor you worked with would only perform an install on an 87+ ECU either. I know that the 87-89 Turbo ECU is supposed to have better fuel maps and timing than the 84-86 Turbo. Not sure about the 87 NA ECU, or why it would matter if you're going to flash the ROM. Pretty sure JWT will upgrade any year ECU.

I'm assuming it's because of the switch from double to single EPROMs in 1987, I was told it's a hardware issue.

The internals of the ECUs are surprisingly different. The earliest ones are very difficult to convert and no one wants to do that. The latest are the best to convert and the middle ones are ok. Look at the Nistune install guide if you want to know more.

I was also wondering what I do with the automatic transmission fluid cooler after the swap. Just remove it?

Flush it out good, get a sandwich plate and use it as a free engine oil cooler? It's not doing anything else now… (edit - I have no idea if anyone's actually done this and I haven't ever even held one in my hands, my auto Z started life as an NA.)

I was thinking it could be used as an oil cooler too. I remember Jason used a NAPA oil cooler for his NA2T and used a Dodge Caravan oil filter for the extra oil capacity. I don't believe anyone has converted the transmission fluid cooler to an oil cooler…yet.

From the LS1 guys:

https://ls1tech.com/forums/conversio…il-cooler.html

Not a Nissan product, but most likely still applies. Looks like the passages may be too small to be effective. Tranny fluid is MUCH thinner than oil. You can try it and report out if you want to risk it.

Yeah, like I said, I haven't actually ever seen one of these in person and thought it might be basically the same as the stock engine oil cooler, but if it's the same 5/16 hard lines that go thru the rad on the NA auto then that's gonna be real small.