joshuaho96

By better shock loading do you mean it transmits more shock loads? Pretty sure it's more torsionally rigid no?

Try goo gone which is a citrus oil.

You can try but I have a feeling the answer is maybe not. The hoses and pipes that hold it to the vacuum box under the plenum are a really tight fit.

The A-LSD controller modifies the slope of the LSD lock pressure vs TPS curve depending on how much lateral g you pull. The more lateral g you pull the harder it locks up: https://sci-hub.se/10.1016/0389-4304(94)90219-4 Seems kind of suboptimal to have an open diff any time you let off the throttle but someone at Nissan thought that was a good idea.

Would love to get a link, I keep using a chinesium harbor freight one and the image is horrifyingly blurry. It was useful for getting that paper towel out of my intake manifold but anything smaller than that and I had a hard time spotting anything.

Those things are so low res as to be useless for spotting leaks unless it's super obvious. It really shouldn't be that hard to figure out the source of the leak. If the actual photo wasn't out of focus it would be pretty easy to see what's going on.

The balance tube has coolant flowing through it. There are a bunch of o-rings that seal up the balance tube to the intake manifold. That can be one leak path. The other is the intake manifold up against the cylinder head. The throttles themselves don't get coolant flow to my knowledge but the intake manifold does. I recommend undoing the harness on the balance tube so you can get a better look at where the leak is coming from. Certainly a lot easier than getting eyes on the back of the intake manifold up against the firewall.

The AWD or A-LSD system uses it to determine lateral g of the car and adjust the transfer case lockup or A-LSD lock pressure accordingly.

The reason isn't that complicated. You just have an early version of the transfer case: https://nissan.epc-data.com/skyline/bnr32/3884-rb26dtt/trans/331/32103M/ 1989-1991 R32 GTRs call for two drain plugs. This was later cost-reduced to one. The transfer case housing was also revised to suit. So you could drain it to get it extra empty of fluid before refilling. Evidently though Nissan engineers decided it wasn't actually that useful to do so.

If you want a knob or a switch/button/etc to adjust the boost any standalone ECU can do that too.

Possible it's calcium additive from Shockproof gear oil.

If the engine is hydrolocked I don't know why you're still trying to start it. The more revolutions the engine turns the more damage you're doing with bent conrods.

I still have no clue how the RB26 TPS closed switch works. As far as I can tell it has one but when adjusting it for the factory ECU you go purely off of the voltage and then unplug the TPS to reset the voltage the ECU decides is the magic number.

I've driven a week on 4 lugs no problem. Probably don't push your luck much longer than that.

-5s generally speaking can do 500 whp. If you push them hard with enough octane and supporting modifications 550 whp should be doable. Solid state relays are the same basic idea as a mechanical relay. You apply a voltage to turn them on and off. The difference is that unlike mechanical relays they can be switched at relatively high frequencies like 60 hz. PWM a normal mechanical relay that quickly and it will die in something like 10 minutes. The idea is pretty simple. You would buy a relay like this one and make sure to put a heatsink or something on it: https://www.haltech.com/product/ht-030202-solid-state-relay-100-amp/ Then you follow the directions for ground switching the pump. In the ECU you would set up a table for your auxiliary digital output that would be PWM percentage with respect to say TPS percentage and RPM. To just get the car running you would just say 30% duty cycle at idle regions, 50% at cruise, then 100% at WOT. It doesn't need to be super precise like injector fuel delivery so just getting it close enough is fine. I recommend looking at this to get an idea for what kind of PWM frequency you need to achieve to keep the pump relatively consistent in flow instead of changing wildly as the relay turns on and off: https://www.portescap.com/en/newsroom/2022/03/controlling-brushed-dc-motors-using-pwm The OEM fuel pump control module is doing the same kind of idea, except unlike this solid state relay it is just switching between resistors on the ground path which means most of the fuel pump power at idle is being wasted as heat in a resistor. Solid state relays do waste some power but far less.

I'd be interested in a new cast block that is primarily interested in fixing the more obvious issues with the RB26 design. Core shift and thin walls is a big one. Another is oil control. Improving the oil returns and feeds is one thing but what would really make me be willing to drop 8k USD would be a lot of engineering/validation devoted to the block/oil pan to integrate internal scavenge pumps and make the engine capable of surviving 1.3g continuous. Being able to confidently push hard on tracks without being afraid of oil surge/excessive blowby would be amazing for peace of mind. Also not having to drill and route even more hoses and all that fun stuff for crankcase ventilation so it retains a relatively factory look and feel would be great. I would also want this block to be first and foremost street-oriented. It needs to just work with low p2w clearance pistons.

Agreed, once you start doing your own work you realize just how cheaping out is actually more expensive in the long run.

-5 turbos are going to be sized for like 600 crank hp. So yes you will need injectors, you will need a fuel pump. If your tuner is using a standalone ECU it will be pretty trivial to wire up either a brushless controller with a flow control signal or a simple PWM with a solid state relay as mentioned earlier. I strongly recommend PWM control because for some effort invested in your ECU and wiring you can keep more things stock and makes more room in what is already a pretty cramped engine bay. If you control the fuel pump well enough the stock FPR is sufficient or a similar Nismo adjustable FPR. Hard wired to the ignition switch/main EFI relay at 100% duty cycle you're going to have to have enough return fuel capacity to absorb over 300 lph of fuel delivery at idle. This depends on your comfort with electronics though. Personally I have no problem wasting my life on code/staring at documentation if it means less mechanical complication but your opinion may differ.

If you try to close the throttle body more by adjusting the throttle stop you're going to cause it to bind against the housing. Don't do this. The throttle stop is set at the factory for a reason and unless you know the correct adjustment specs it's a bad idea to try and mess with it. I'm speaking from experience as someone who has messed with that stuff before. I would only do it on an engine where you're installing your own custom throttle/intake and therefore the adjustment spec is no longer valid. Once you have ruled out external vacuum leaks you have to start chasing internal vacuum leaks. This is considerably more annoying. What I mean is stuff like this where you have some old worn part allowing air to bypass the throttle so the ECU can see the excess air but it can't control the idle: I had a mildly high idle on my RB26 and some combination of having the intake manifold resealed and the throttle bodies rebuilt likely went a long way to curing my high idle issues.

https://nissan.epc-data.com/skyline/bcnr33/3935-rb26dett/trans/321/32006M/ https://tfaspeed.com/products/nissan-skyline-r32-gtr-gts-4-reverse-switch-assembly-32005-21u1b-jdm-genuine https://tfaspeed.com/products/nissan-skyline-r32-r33-gtr-r32-gts-4-neutral-saftey-switch-32006-31g01-jdm Looks like rearmost should be the neutral position switch. The one closer to the bellhousing is the reverse switch.

It's hard to reproduce the exact factory colors and feel, but alcantara is pretty much the same general idea. It's all polyester or otherwise plastic-based suede imitation fabric. Robson leather managed this with just alcantara so that's probably the way to go: Keep in mind you will also need to find someone who can figure out how to fix the foam which is almost certainly collapsed with age. If you aren't wedded to the exact OEM look and feel you could do something like the Nismo seat covers which is plastic-based leather on the bolsters and headrest and alcantara in the center. I wouldn't buy the Nismo seat covers, kind of a waste of money unless you really want the Nismo logo for some reason. Garage Active makes something similar for half the money so the margin there is pretty tremendous. Personally I think the OEM airbox is a good idea mostly because the HKS mushroom filters don't actually filter anything and sand in your engine isn't great for its longevity. You'd have to use the OEM paper filters or something comparable though and it will likely reduce power output if you're going for huge power. My recommendation if you want to rewire the fuel pump to reduce fuel pressure regulator load you should use a solid state relay and a new wire to your standalone ECU so you can adjust duty cycle. The factory FPR is super dinky and can't bypass a lot of fuel. Even big aftermarket FPRs have limits, if you throw 500 lph at one and expect it to bypass all of it at idle you're probably going to have higher fuel pressure at idle. If you plan on throwing out all of the OEM fuel system this is less relevant but then you should consider how you're going to replace the OEM pulsation damper and all of that fun stuff as well for higher flow designs. As others have said a lot can go wrong with cars this old. Don't parts cannon everything. Look at things as they are and try to get to ground truth when diagnosing problems to understand the causal chain between a problem and the resulting symptoms. Otherwise every little problem will drive you insane.

I still can't believe Nissan wants 5k USD for an N1 block now. There's no way it's 3x better than an 05U.

Do you have the spec sheet for the switch they provided? Looks like there's some writing on the switch so you should be able to look up the part.

Stock boost wiring is fine, it goes to the ECU. If you don't want to cut the plugs you can make an adapter from the OEM harness to the new boost solenoid. Contact Wiring Specialties to see what they can do in that regard. As others have mentioned you can just shove a bolt or something into the end of the hose to cap it off if you don't want to put a cap in at the pipe. Personally I'm a big fan of retaining OEM connectors where possible after seeing how much people want for new ones or how much Nissan wants for new harnesses now.

I recommend using the EPC to answer these questions in the future: https://nissan.epc-data.com/skyline/hr33/3927-rb20e/body/650/65100/ https://nissan.epc-data.com/skyline/ecr33/3909-rb25det/body/650/65100/