GTSBoy

This is not true. 9 psi on a 25 should give no more than 180 rwkW, probably only 170. Yup. Also yup. Won't. Can't. Need.

Toe out would be way twitchy. Zero toe should be very easy to disturb. Toe in should be more stable. Be aware that static toe, as measured on the rack, may completely change when the vehicle is moving, particularly if you have stuffed bushes in any of the arms.

The differences are mostly like this. Type M differences: Different steering wheel Different body kit Bigger brakes (these being the normal 280mm x 28mm 4 pot fronts, plus the 2 pot rears). Slightly different suspension Engine and driveline are the same And they didn't have blue dials as standard And the motorised chin spoiler maybe. Although a lot of things like that were options that you could put onto many cars. For what it's worth, the vast majority of R32 GTSt are type M.

Surely incompatible elements there. Blue dash black dash is just early/late.

Disconnect the battery again and see if you can lock it with the key. That will tell you if it is doing it with power of with a "spring". If it is lockable without power, then don't leave the battery connected, or you will likely drain it or maybe even burn something. Go check all the fuses. Both under the dash and under the bonnet. Find any that are blown and replace, then consider what works and what doesn't work. Be prepared to take it to an auto-elecctrician, because you have a number of other systems in the car (the ECU, the ABS/TC CU, the HICAS CU) that could all be grumpy with you for smashing the electrons in backwards. They don't usually take kindly to the nasty transient voltage spikes you get when you make and break backwards battery connections.

The wiring diagram is in the R32 GTR workshop manual which is freely downloadable from a number of googlable sources.

The issue with that is that once you outlay the cash for new coils (OEM or Splitfire), and possibly a coil harness, you are a significant fraction of the way to a real upgrade. Even if you limit yourself to Yaris coils or similar, you can do it for the same sort of $$ and a moderate step up in coil energy. But if you do R8/R35 type coils, for about 30-40% more money you have a massive increase in coil energy. The only penalty to doing the upgrade is that you need to be able to compensate for any dwell time changes in the ECU. Not possible with fully stock, but easy with aftermarket ECU and even doable with Nistune (IIRC).

Yuh, somehow Mishimoto seems to have picked up a reputation as being legit Jap OEM grade or HiPo stuff, when it is just another generic yum cha. And not always good yum cha either.

You have R33 TPS. Does it even have the idle switch? If not, you'd need an R32/Z32 TPS. You can't really interpret AFRs when an engine is stalling. When the fuel isn't getting burnt, analysing the exhaust gas is a waste of time. As for the then and now scenarios - things change. Leaks develop. Injectors get dirty. Etc. That's why engines have adaptive shit on them (like the IACV and the ECU given the idle switch so it knows when to use it) - to get them past these changes and keep working. When you "tune" an engine to suit a very specific set of conditions (BOV/no BOV, certain level of cleanliness of the TB/IACV, etc) you leave it exposed to changes in those base assumptions. You either attempt to maintain the conditions of those assumptions or you prepare to compensate (retune) for them as the changes mount up.

I looked. This page says the Z32 definitely has an idle switch https://conceptzperformance.com/wiki/index.php/Throttle_Position_Sensor

I think that's your problem. Compare that with what I wrote in the post above. Then do some research as to what the Z32 ECU wants to see. If the ECU wants a switch, then with no closed throttle switch input to the ECU, there's no benefit to having the TPS set "correctly" to give the right voltage. The R32 ECU does not look at the TPS voltage at all - it only exists for the transmission controller. Hence why I suspect the Z32 is same same. You'd probably be better off with a Z32 TPS and whatever wiring change might be required to hook it up properly.

f**k off the chip tune. It is 2020, not 1999. Nistune is the superior solution, even with the difficulties associated with using a Z32 ECU on a vanilla RB25. Nistune has come a long long way to making that stuff work better in the last few years too, so would be worth your reconsideration. Basically, this stall behaviour is the ECU not being able to control the engine speed when the throttle is closed. We normally point to the IACV because it is usually dirty/stuck. And just because you have cleaned does not prove that it is working. But the ECU can also struggle to know that it should be trying to maintain engine speed with the IACV if it doesn't know that the throttle is closed, hence my question about the TPS. I don;t know for sure about the Z32, but seeing as it is the same era as the R32, I would expect that the ECU wants to see a throttle closed SWITCH, not the analogue value (~0.45V) that is required on later ECUs (ie, RB25). So, I ask again, what TPS do you have on it?

All 25s from S2 onwards have coils with inbuilt igniters. So the benfit is not from that. It is just from being a much stronger spark (the R35 conversion, that is).

What ECU? How critical is TPS adjustment to the idle on that ECU?

Except aero drag is already becoming dominant at that speed and you will almost certainly do better at 90 km/h than 120.

You haven't met my sister-in-law, clearly.

What does this mean? Mishimoto is genuine nothing.

I don't know that it is harder to get parts for a Neo. What parts? 2nd hand or new? Electronics or pistons? Skipping past that, on the basis that it not the reason make your choice, the logical points are; The Neo is a better engine. It makes more power stock, because of better head design and slightly better management. It qualified as a low emissions vehicle when it was new, because of those changes. It has solid lifters which makes it better for high revs than the vanilla 25, although they are shim over bucket (unlike the RB26's shim under style) which does make them a little bit more prone to spitting shims if you do stupid things without taking that into account. They have the N1 oil pump stock. They use RB26 rods, which are a little better than vanilla 25s. They are newer, so you are a little more likely to get one in better condition than a 33 motor. The vanilla 25 will be easier to put into the R33. The wiring will be easier to achieve. The Neo has some sensors and connectors and the like that the 33 didn't have. So it is extra stuff that you have to allow for. But.....either way, you're transplanting a different engine in, so you have work to do regardless.

That's nice.

Don't waste your time putting an RB20DET into it. For very nearly the same up front cost, and exactly the same work, you would be better off putting a 25 into it. 1000x more driveable than the torqueless RB20 (as a street car).

Not necessarily rubbish. Mine is set up with zero toe and it is really nervous. Good fun and keeps me on my toes.

What is the rear toe after the alignment?

My bet is that the radiator or water pump or state of bleeding of the system are sad.

There's at least a big chunk of the problem.

Is the AC fan working?