joshuaho96

Something to keep in mind with doing a blow-through setup is that it will likely increase MAF maintenance requirements, engine blowby with the right particle size can get through the dirt/fluid bypass that the card style hot film MAFs often have and deposit on the sensor, affecting the calibration. I have no personal experience to say whether this is a problem with the modern R35 Hitachi sensor but like anything in engineering you're picking what compromises you're willing to deal with. Putting the sensor closer to the intake plenum improves transient accuracy and more accurate IAT but it all comes at a price.

Good to know, when I was thinking about this issue for a while I had a feeling that was the case but I checked all the connections from the PTU to the coils anyways. My circuits professors are probably shaking their heads right now.

R34s shouldn't, but the logic is the same. The ECU sees the primary side wiring from the ECU output all the way out to the coilpack pins and back to the ground point. If it sees open circuit it sets a code 21. Short circuit you would probably detect pretty rapidly regardless of whether the code is reported or not.

If you want to conduct this test without the work involved in pulling coilpacks then you can use Consult to disable individual cylinders, I use the active test section of NDS1 for this: In theory you could use this to figure out exactly which coil is misfiring under load but at least in the case of an RB26 the coilpacks lack ignition feedback signals so the ECU cannot detect any issues on the secondary windings, so you're going to be spraying quite a lot of unburned fuel into the exhaust. A misfire is really not that hard to figure out though, your engine is going to run quite rough from the imbalance in combustion forces. I say this a lot it seems but NDS is a super useful tool for diagnosing problems with these cars. In the case of your fluctuating idle just reading the ECU logs would give you some clue as to what's going on, such as weirdness in the O2 sensor signal or MAFs.

Yet another bump. I recommend buying new hoses for your brake and clutch master booster because my brake booster hose is rock hard and split at one end. I'm going to live with it for now but the replacement has been ordered. The plenum intrudes and takes every little bit of space that the factory clutch booster setup needs so the Nismo manual for this part details how you need to remove the clamp that goes around the check valve as well as the bracket that holds the hose and check valve straight. You will still need the nut and lock washer that goes to the clutch master cylinder, just the bracket is removed. The rubber insulator on the check valve clamp is also retained on the check valve as far as I can tell, presumably to try and keep it from grinding into the plenum. This thing has been a ton of work and money, so hopefully the long runners at least do something for low RPM response. It's definitely not going to be a huge difference but just looking at a similar kind of experiment I'm optimistic:

I found the same link through google and it doesn't seem ridiculously sketchy at least.

Code 21 means the ECU isn’t seeing the right resistance on one of the coilpack primary side circuits. I got it once when my ignitor unit had a slightly loose connection.

If your car has ever been driven in the rain it is all but guaranteed that the highlighted area under the trunk is going to have surface rust. Nissan went super, super cheap on undercoating starting with the R33s and it got even worse in the R34s. You'll notice the undercoated area has no surface rust but the area that is merely painted with what looks like primer or base coat tends to show surface rust easily. You can arrest the spread of rust in those areas by using a lanolin-based undercoat and it won't matter anymore, the oily grease will stop rust from progressing further. If you really want to go crazy you can do what I did and have the entire car taken apart by an R-chassis specialist so they know what NLA parts to treat like platinum and have the subframes/suspension components powder coated and the entire underside resprayed with urethane undercoat. At that point though we're talking about spending the value of the car itself in restoration.

Thrust bearing vs ball bearing in a small turbo around the size of the GT2860 is supposedly not a simple trade, supposedly ball bearings have lower shaft speed limits than journal bearings. Of course ball bearing has far superior transient performance because there's a lot less oil causing drag in the center section: Turbos are more than just their bearings, it's important to keep in mind what their compressor and turbine maps look like. I wouldn't bother with the GTIII-2530 when the GTX2860 gen 2 exists and isn't HKS-taxed but the GTIII-SS in particular has no equivalent on the market as far as I can tell. That's a very small turbo that doesn't go much higher than 20 psi at high RPM in an RB26 before the 0.54 A/R turbine chokes it. R34 ceramic turbos are probably the most responsive low mount twin turbos out there still but I didn't want something that could blow up like the stock ceramics.

I believe Motec supports GDI now. So if you want to live out your dreams of doing embedded system development you can buy one of their ECUs and spend your life re-implementing basic functionality. Another option is maybe a Mine's VX-ROM tune.

https://www.importavehicle.com/blog/check-engine-light-diagnostic-trouble-codes-for-1989-to-1994-nissan-skyline-gt-r

Looks like they put some more details on their Youtube channel. It's interesting how they actually bothered to completely rethink the airbox/intake piping end to end, usually those are left as an exercise for the reader to complete. Anyone know what that AVL capture is showing? I have strong doubts it's actually from an RB engine, would not be surprised to know if it's a single cylinder research engine.

RB20DET O2 sensor for an HCR32 GTST Type M would be 2269073L11. For some reason it's extremely expensive and not shared with many other cars but that's what it is. I can't find an aftermarket equivalent either. Terra Firma in the US claims that an NTK replacement will work but they don't say what it is: https://tfaspeed.com/products/replacement-oxygen-sensor-for-nissan-skyline-r32-gtst-gts4-gts25-rb20-25det Checking Kudos Motorsports it's likely NTK OZA726-EE2 which is used in the Pulsar and B13 NX.

You can check for codes in the meantime with a jumper wire.

https://nisscan.com/NDSI/index.php?content=supportedadaptors Looks like it’s the right one but not sure.

You can achieve something similar with just the standard intake VCAM, especially if you go for the full 50 degrees of cam advance. I often see tuners unfamiliar with VVT just doing the full throttle pulls and interpolating from there which causes them to miss the bigger benefit of EGR at part load. Exhaust VCT does help, just not as much as you'd hope. The twin injector setup I'm pretty sure their idea is to deal with a few different issues going on. One is that there's basically no such thing as an 800 cc/min twin spray modern injector on the market. To get there with commodity injectors (not some ridiculously expensive Bosch Motorsport thing that you can't actually buy) your options are either a Denso injector with a single cone spray and 6 hole diffuser plate at 850cc/min or the Bosch 040 980cc/min 7 hole diffuser plate with single cone spray. That's at 3 bar, obviously you can bump the fuel pressure of a smaller injector but even at 5 bar you probably don't have enough fuel. The better the spray pattern (the better the fuel avoids the intake walls), the less fuel that has to be accounted for in all kinds of transient scenarios like cold start, transient throttle, etc. The other issue is dynamic range. Smaller injectors are fine for this but a big injector these days may still have to idle rich just to stabilize the fuel delivery instead of having the idle chase itself all over the place. With staged injection they could just fire a single injector at idle and only bring in both injectors when the pulse width is large enough to run both of them in the linear regime. One thing I have been thinking about for some time now is whether the Bosch 997.1 turbo injectors (0280158123) would be able to fit the RB26, combined with a 5 bar FPR and a fairly heavy duty pump like the DW440 brushless it should be able to sustain that high fuel pressure even with a decent amount of boost to get right around 800 cc/min of flow like this but without any complicated injector setup. It's a 3/4 length EV14 injector with extended tip so it's a bit longer than the traditional 040 980cc injector but otherwise it doesn't seem unreasonable to me. Don't get me wrong, I think what HKS is doing is really interesting, I'm just highly skeptical that they will actually bring the important pieces to market like the exhaust VCAM or passive TJI retrofit.

Flasher unit is in the dash, number 52 in this image next to the center console stack, it's next to the buzzer to remind you to remove your key and "circuit breaker" and is a black 3 pin relay. Not sure how you actually get to it though:

HKS talked about the engine last year I believe. It mostly looks like just a conversation piece for now. Can't tell if the mounting bracket for the electronic wastegate is some kind of weird 3D printed metal or plastic but I doubt that will actually work even as an engine dyno proof of concept. Those exhaust manifolds look like a prototype and will likely not last long either. The dual chamber plenum is probably the closest to reality and the dual 400cc injector setup is pretty interesting too. I don't know why they didn't just try and figure out a single injector with two cone spray doing 800cc/min instead but maybe that's too boring. You can basically achieve that just by taking a current mass production EV14 630cc injector and bumping fuel pressure to 5 bar. I'm also super skeptical of the fuel economy claims. I doubt they can do it without cooled EGR to actually realize the passive TJI system they're proposing. Otherwise the sheer strength of the combustion event will likely beat the bottom-end to death.

It sounds like you figured it out but for future reference a Consult cable + Nissan Datascan 1 will be able to read out all of the data from the stock ECU or a chipped/Nistune variant of it.

What does the ECU say? Does it get an RPM signal? Is it receiving the starter signal? Does it see acceptable battery voltage? Does it report any codes? Don't parts cannon a no-start condition, engine not starting is a pretty simple issue to debug. Either it's fuel, spark, or you have a mechanical issue causing excessively low compression.

Try various orientations until it releases? I don't recall having any issues with those clips.

Don't decat street cars, end of story.

Additional note: The brake + clutch vacuum booster pipes are an absolute pain in the neck to get in compared to the OEM lines. You must use the Nismo-provided pipes to clear everything properly. I would recommend maneuvering the pipe to stick out between cylinder 5 and 6 as it should before you put the collector on the intake manifold/ITBs. You can do it afterwards like I did but expect to do a lot of maneuvering to figure out how to make it happen, you should expect to have the fuel filter unbolted as well as the boost solenoid and fuel injector resistor pack taken off to make more room. Getting the gasket in place is an absolute pain in the neck when the coolant pipe mounting tab is actively pushing this pipe out of place. Also, Nismo includes a replacement part for the oil pressure sensor bracket that connects it to the vacuum/coolant pipe that is directly above it. I assume you need to put this bracket on to get everything to fit correctly, presumably the spacing is slightly different relative to the OEM plenum which will cause this coolant pipe to not fit up correctly with the air chamber under the plenum. Do this before the plenum goes on instead of after, it is much more annoying/difficult to do it when the manifold + collector is blocking access. 10mm u-joint and 12mm u-joint quarter inch sockets as mentioned are mandatory for this job. I cannot imagine how you would even attempt to do things like bolting up the brake/clutch booster pipe without one. Even though a wrench will get on the bolt, I only have like a quarter turn before I'm hitting something and a ratcheting wrench will be too big to clear the pipe.

I managed to do it. I highly recommend a 60 degree open-ended wrench/spanner for this job in conjunction with a 12mm u-joint quarter inch socket for the rearmost stud at the bottom of cylinder 6. Also as I mentioned make sure you put the dowels on the ITBs, not the plenum/collector, otherwise you won't clear the studs. It will barely clear and maybe scratch the gasket face a little around the bolt hole areas.