GTSBoy

Yes. Be very gentle. The TC sheath is very thin stainless (or inconel) and is packed with a dry mineral around the wires inside. You should be able to reshape it a little bit, so long as you don't end up crimping it. Try to support the sheath as much as you can (like you would if mandrel bending something) to prevent it folding.

Oops. :p Probably explains the GARRETT cast onto the comp housing then, hey?

They're not "called" anything. They were made by Hitachi as an OEM supply to Nissan. Nissan think of them as their Nissan part number. Hitachi probably call them by the contract number with Nissan. To the rest of us they are; The RB20 turbo, The RB25 turbo (often called the 21U, and note that I typo'd U21 in my previous post) The RB25 Neo turbo. There are a few little variations in flavour there, in that the nylon compressor wheel made an appearance on the later 21U turbos, and the OP6 turbine housing also appeared on the VG30DET turbo, but the compressor was different to the RB25 turbos. The only thing that is at least consistent is that I _think_ that the ceramic turbine is the same piece on all of them. I think there was only one design.

And quite possibly adhesive/sealant squirted along behind, depending on who/what was responsible for putting them on last.

Nope. Mostly wrong. All RB20,25 turbos and all VG single turbos are Hitachi made, with a T3 flange. So they are not T25 or T28. Nor are they really T3. They have a T3 flange and are in the ballpark of T28 size, or thereabouts. But they are not Garrett and therefore they are not T anything. The OP6 housing is larger than the U21 housing. Yes. CA & SR turbos are neither T25 nor T28. They have a T28 flange on them, yes, but again, they are not Garrett, therefore they are not T anything. They are all ceramic.......except the CA/SR turbos, which are not.

Ignition coil is a possibility. As is dirty/cracker dizzy cap, or worn wipers/posts inside it. Could be a cracked head. They used to miss like that in VLs with cracked heads, and they were often worse when warmed up.

World of hurt. The sage old advice we give people who want to do this to a Skyline is applicable here, multiplied by about 100. Sell it. Buy a manual car.

There is no difference between plenum and comp housing on an ITB 26.......well, there is a small difference related to the speed of sound and the propagation rate of the pressure signal. I think Nissan did it in the plenum on the 26 because it was a reasonable place to pick up a signal from both turbos. That's all.

Shouldn't have to change anything. They are the same thing. Auto ECU will happily run a manual. GTS4 ECU is same same as RWD. If the GTS4 ECU is not running your engine, it would suggest that there is either something wrong with it, or perhaps it is already Nistuned or otherwise reprogrammed for different sized injectors/AFM or something.

Old stock at Nissan is the only hope. But you can't just "change" the ones around the rear windows. That's a body shop exercise.

I've written thousands of words on the reason on these forums before. Hooking it up to the manifold is a good way to make the turbo work way harder than it has to under part throttle operation. On some turbos, this could actually lead to overspeed failure. At least it will lead to higher EMP than is necessary.

It's all the same shit.

But, in these days of Arduino, surely that's a triviality.

No, and no.

Just install the new turbo and don't set the boost any higher and don't have it ramp as fast as it could and you should be able to live on the existing tune.

You're on your own then mate. You have ventured into foreign territory. If I had to guess, if there's no sign of burnt tracks from the injector pins, then you've likely killed the transistors that run the injectors. Odd to kill them all though....

^this

What ECU is it? R32 or Z32 ECU are the correct choices for RB25 and they don't take a Type 3 board. They are Type 2.

Sounds bad. Open the ECU up and look for burnt tracks or transistors connected to the injector pins.

You're on the north side Adam? Go see Brenton at Fours N More. He'll hate me for sending another dirty Nissan to him, but he should be able to sort you out.

Take it** to a brake workshop. Give it to them with a small handful of money (like, <$200 worth) and wait a couple of days. Presto, rebuildo. ** The booster.

Have you at least got Nistune in the ECU so you don't have to put up with fault codes from butchering the TCS? And what makes you think that there should be 12V? Most ECU sensors are run from 5V. Plug your R34 TB back into the loom and see what you see from that. Then go forward from there.

And what state is the charge at? Have you considered that it might have a leak and has let some gas out?

Same as every other such question. Get it inspected thoroughly. If it comes through that without any red flags, just buy it. None of them are going to be perfect. They're nearly 30 years old now. And whatever red flags come up, just pay accordingly.

You can buy this stuff just about anywhere. Ebay, Amayama, Kudos, Just Jap, etc etc. You are looking for bushes for your front upper arms and you are looking for HICAS rack ends (if you want to waste you money putting a useless system back into service) or a complete HICAS delete kit if you want to improve the car.