GTSBoy

This is a Consult port The 3 important wires are those that connect to RX, TX and CLK. They are AF01, AF11 and AF32, respectively. Colour codes are also shown. This is the same Consult port, now with the wiring down to the W-2 connector shown. That's the ECCS harness, which proceeds to the ECU. You can see the same wire numbers turn up on the RHS of that plug. But you don't have to follow it from here, because.... This is a snip of the ECU, showing those same wires on pins 21, 22 & 31, in order. There's also the CHK pin on 47, which is the one you can short to earth at the Consult plug to convince the ECU to go into diagnostics and flash the check engine light to reads codes. You can see CHK in the Consult port image. But that would assume that the ECU has been wired to the check engine light properly.

It's got an RB25DET (at least) with a bigger turbo on it, which would explain it being fast. The body appears to be a bit rough - at least the paint does. Not enough other photos to see. The chassis is an unknown. Could be anywhere from $5k if it has a lot of problems out to high teens.

RB20DET ECU has an LED. It's next to a knob that you use to trigger it. You can also wire up the Consult port. Easy as. The RB20DET ECU wiring diagram and pinout tables are freely findable with 2s of googling. It's a serial connection - there's not a lot of pins to hook up.

Yeah, but to avoid wasting half the potential improvement, the budget really needs to include an AFM and injectors, likely a fuel pump, conceivably a clutch. But what's another grand or two? I otherwise completely agree.

Not really. A big aftermarket manifold might improve your top end power a little bit compared to the stocker. But only a little bit. So little that you'd be hard pressed to tell the difference. I mean, we're talking the difference between 195 and 200 rwkW. There might be a small improvement in spool response. Or there might be a decrease in spool response. Depends a lot on the specifics of the manifold that you put on. One with big runners designed to support heaps of flow/power will likely suffer in spool. One that is carefully designed to get the gases to the turbo efficiently might improve your spool, but won't support as much flow and power and is therefore unlikely to be something that many manufacturers would have on their list of existing offerings. No-one's really going to spend up to $2k on a manifold to optimise the response of a stock sized turbo. And your car is unlikely to be "at least 200rwkW" right now. It will be lucky to make a real 200rwkW at that boost on the stock turbo. Mine makes a trustworthy 190rwkW with the same mods (different ECU, but still, tuned). I could possibly give up some safety in the tune to get it up to 200, but they're really not going to go a lot higher than that. Optimistic dynos not being part of my consideration, of course.

Nope. It's stainless. It will retain its strength until ~1000°C.

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.