joshuaho96

With an EJ25? The limit for ringlands I thought was due to combustion chamber pressures. While any one knock event can instantly kill the pistons at 250 kW to the wheels or so my understanding was even normal combustion could still damage the piston ringlands. Then from there the next thing to break would be conrods.

I checked online and Garrett seems to suggest that at warm idle minimum oil pressure at the inlet needs to be at least 15 psi and at redline no more than 45 psi. Can you really separate oil pressure and flow rate in these systems? I assume that when the spec says a certain oil pressure it implies a certain resulting pressure drop across the CHRA and a resulting flow rate.

The STI in particular still had an EJ engine in it. It pretty much never had the ability to take big power. The entire block flexes easily and is not conducive to a long and healthy life with big power. The factory top-mount intercooler heat soaks very easily. The factory cast pistons put the compression ring very high up making it very vulnerable to knock in order to reduce crevice volume for emissions. Considering how weak the block is the 2.5L EJ257 used in the US is basically not designed to ever be stroked as the rod ratio is already on the low side. Normally not a problem, plenty of Honda engines run pretty extreme rod ratios but an EJ block is a delicate thing. The S209 in the US made 340 hp using an HKS GTIII-RS turbo and that is probably the absolute limit of what Subaru/STI powertrain engineers were comfortable with warrantying.

¯\_(ツ)_/¯ The Kinugawa bolt-on turbos for RB26 are far larger than the -7s, it also lacks the HKS logo for extra JDM tyte points for cars and coffee. The goal isn't really to go for big power. The GTIII-SS obviously is down on response from bearing drag but it's a smaller turbo than the GT-SS. It's pretty much the smallest turbo readily available for the RB26 other than the factory ceramics. It's not going to impress anyone with numbers but if that was the goal I'd buy a Lucid Air.

There's a lot of drama that led up to that. Tomei USA started using different sources for camshafts and other parts and sometimes it wasn't equivalent in quality to the Tomei JP brand version. Supposedly they stopped paying the JP branch as well. You can look up Real Speed Engineering to see Tomei USA parts being sold in Japan. Personally I stay away not because of this business drama in the background but because multiple people have posted issues like the Tomei USA cams physically not fitting in the head and head gaskets failing on the very first engine start. Maybe one is a fluke but multiple people going to different machine shops and generally pretty knowledgeable about the requirements around surface finish/flatness/etc for MLS all having issues is too much for me to even bother risking it.

Doesn't the turbo call for a specific oil pressure at the feed? So in theory at least a super high pressure oil pump will need more restriction and a low pressure oil pump would need less restriction. How much that actually matters in the context of real parts I don't know.

I still debate what to do there honestly, the original turbos were covered in either a ton of blowby from the decades or seeping a little from the seals and I couldn't ship them with the car anyways. As far as I can tell nobody really rebuilds turbos with the factory ceramic turbine either. I'm also not sure that anyone cares about having the factory ceramic turbos, even for weird obsessives like me. Then again you have the Contempo Concepts of the world trying to source series 1 R32 steering wheels because the later revisions have slightly wider spokes which is unacceptable to them. I'm pretty sure you're right but it's kind of interesting to see the kinds of results that this tuner got with the magical beans. They also report differences between the HKS 2530 turbos and the Garrett -5s which is interesting: How real any of this is an open question but they sure sold me on the HKS magic bean journal bearing nuggets. Well, that and a lot of staring at Kansai Service/Midori Seibi dyno charts to get a sense for how they compared to the other relatively low power bolt-on turbos.

I like my gloves, but I'm a desk jockey that gets sore all over after rotating my tires and bleeding brakes.

A lot of workshops I talk to don't even do intake plenum/collector with the engine in the car.

Removing or installing the twin turbo setup with the engine in the car is a pretty miserable experience. I have no idea why anyone would bother with that.

Nismo R3 turbos for the Nismo logo in the compressor housing. It adds 50 horsepower at least.

I wouldn't allow the engine to turn until you've verified that you haven't gotten a bunch of ceramic bits from the turbine going backwards from exhaust gas reversion. Letting off at high rpm you can see the manifold pressure reach high levels of vacuum.

I haven't really heard of these venturis being replaced very often in most R33s. For a 450 lph pump it may be necessary but with the 276 lph drop-in pumps it's probably not. From what I see online people don't report issues like this on the R33: https://www.skylineowners.com/threads/help-identifying-this-part.317169/

The design seen in the OEM part would definitely not pop off even under boost. Pretty substantial lip with a hose clamp to apply pressure to keep it from moving. The trouble is finding an aftermarket pipe that would replicate that design feature.

https://www.bosch-motorsport.com/content/downloads/Raceparts/Resources/pdf/Data Sheet_68749835_Electronic_Throttle_Body.pdf It's really strange to me that their drawing here shows what I would expect, which is a lip to keep an intake pipe from slipping off and a flat section for sealing properly. This is 0280.750.101. Digging deeper into it apparently this is not what is being sold widely, rather it's whatever is being used by Porsche and other vendors. Looking at the EPC number 3 in this diagram is the pipe that connects up to the front of the throttle body: Edit: If you look at this guide showing how they clean the throttle body it's clear to me that the pipe has a lip in it and then a hose clamp that applies pressure to keep it from pulling off: https://www.planet-9.com/threads/how-to-throttle-body-cleaning-and-gdi-intake-cleaning.248159/

Looks like the back of it is just flat, so you'd have a gasket and then some bolts that hold it to the intake. If it's anything like the other DBW setups I've seen it's just a hose and hose clamp that goes over the front of the throttle body and the lip is there to keep the hose from slipping.

Doesn't this affect the brake bias?

Easiest way to find it is to pressurize the system with nitrogen and see if it loses pressure. Or pull a vacuum and see if it loses vacuum.

Pretty sure this is the correct thing to do if you know that there will be no downstream relief valve. Looking at the RB20 housing I don't see anything like the relief valves in the RB26 housing.

With an external oil cooler I would imagine that you want a bypass both for filter pressure and the oil cooler. In the RB26 the factory housing has a relief valve on it for either scenario. I'm pretty sure that the block itself does not have the relief valve.

I know people that have had issues with Tomei USA head gaskets. Hard to say whether it's the gasket or installation error though.

If you have a weird thing about how you don't like the insane range of the 320 km/h Nismo meters and for some reason their coloring of the 8-9k range as yellow rather than redline I'm pretty sure you can just adjust the speedo calibration resistors and replace the gauge face with whatever corresponds to your desired calibration. You could make a 300 km/h speedo that way I believe like the Impul ones that were basically identical to factory other than the speed calibration change.

Even if you go to an aftermarket crank trigger you can still use the factory cam signal. Unlike the aftermarket solutions the OEM cam signal has one tooth for each cylinder and the width of each tooth is different so the ECU can tell exactly which cylinder just hit TDC. The utility of this is probably a little questionable when all you really need is one tooth to indicate that the cam has reset but I'm sure Nissan engineers would never overdesign something for questionable benefit.

If it is low on refrigerant definitely do not just recharge and keep going. Leaks let moisture into the system which is a good way to saturate the receiver/drier with water and start damaging the compressor and other components with internal corrosion.

The hose you clamped is not just for the AAC valve, there's also an intake air regulator/cold start valve in there that affects your idle: Verify that your cold start valve is actually getting power and closing after some time. To some extent this is just guessing because your intake is clearly not stock and it's unclear whether the routing of your vacuum lines is still the same as factory especially because your crankcase vent lines are gone. I also must emphasize that as a general rule once you set the AAC idle screw on an engine that is otherwise mechanically perfect (no leaks/etc) you should never ever touch it again. Your idle getting out of whack is never going to be fixed by touching a screw that has extremely limited control authority, and it is never a good idea to band-aid over some issue with air control by touching that idle screw even if it does work.