joshuaho96

Turbos don't require pulling the motor apart so that's "easier". I would recommend the Nismo R3 turbos instead if you want to do stock twin turbo. It doesn't make as much power as the 2530s but it's only like ~50 whp off the mark and should have better response (ball bearing CHRA, slightly smaller turbo). A local that went with a Garrett G30 and 6boost manifold recently nearly burned his car to the ground after the hood insulator started melting and and burning so if you go single turbo I recommend doing a lot of research and validation work to make sure you don't do the same.

That's what the people want, unfortunately. We can argue about whether this is cultural or marketing but in the US people like big SUVs because they want the capability all in one vehicle.

There's absolutely no way the turbine is nylon when EGTs peak somewhere in the region of 800-900C. The compressor can be nylon.

I mean yes, if you're starting from scratch on an unknown engine yes you don't need to be doing all kinds of math in the background but if you're doing relatively minor changes like AFM + injectors + boost up with some aftermarket turbos it takes quite a bit of math if you want to do something like maintain OEM fuel + timing tables but compressed and then a bit more load scale up top. I think I've spent too much time working on big engineering nightmares though so I'm a big fan of trying to constrain the scope of whatever work I'm doing as much as possible and trying to get it right before moving on. For example, a local owner just did the usual E85 + single turbo conversion to his R32 GTR and nearly burned his car to the ground doing some spirited driving up the local mountains. Turbine is unshielded and too close to the hood insulation. It's tough to balance "just get the project done" and "seemingly small details can cause massive setbacks I'm not willing to deal with".

Nistune needs something like an entire excel spreadsheet in which you build an abstraction layer that converts everything from real units you can actually measure into all of the various tables. The number of unexpected dependencies hiding in how the Nissan ECUs do math is a pretty impressive optimization trick for 8-bit MCUs but good god is it awful to actually work with in practice.

Kind of surprising, with cars this old I've seen a lot of them suffer from high idle due to internal vacuum leak. Fuel trims look fine but the cold start valve just wore out from all the heat cycles and won't close up all the way. Rather notorious issue in some models of the Toyota 4Runner:

IACV has an air bleed plug in this part of the engine manual. I'm guessing if it isn't bled it will cause weird idle behavior as the cold start valve won't get hot enough to close properly at the usual rate.

If you fully flushed and filled it's probably good for 5 years. I would not push it any further than that. Generally speaking coolant is more by time than by mileage. Rust wants to happen whether you're driving it 50,000 km or 80,000 km.

Modern transmissions like the 8HP lock up as low as ~12 km/h. And they will stay locked even with full throttle in gear. Far, far cry from the days of 3/4/5 speed automatics when they only locked up on overdrive gears and even then only if you didn't put too much torque through it. Manual transmissions are pointless unless you personally enjoy shifting gears.

Now that you mention it I can see those too. More subtle. The lighting and low resolution makes it hard to assess super well what's going on but what is visible is bad enough to pull the motor.

To me that looks like a rust ring in the bore. An engine that has sat for too long in humid conditions without fogging oil in the bores?

Stock ECU has compensation, you won't damage the engine. Personally I recommend getting an acceptable catalytic converter, it doesn't need to be OEM and super expensive but a cheap universal one to keep it from being super obnoxious to be around. Decatted cars smell pretty awful.

It is correct: https://www.amayama.com/en/genuine-catalogs/epc/nissan-japan/skyline/er34/6617-rb25det/engine/220 Looks like you can get one for 50 USD each from the UAE which is a pretty good price IMO.

Ah yeah I forget we aren't talking about an RB.

Pretty sure the factory assembly doesn't have any gasket at all, just RTV.

There aren't boost creep issues, it's not engineered around the restriction of the cats but if you haven't tuned the engine a full decat + exhaust can flow enough air to run off the end of the OEM load scales and you will get a pretty substantial reduction in ignition timing as a result. I recommend using DFCO, avoiding ignition cut limiters, and avoiding popcorn tunes along with running a cat unless you enjoy a perpetually soot-covered and potentially burnt bumper.

It really helps that light duty vehicles have absolutely appalling average efficiency due to poor average load. Like 25% average brake thermal efficiency when peak is somewhere around 38% these days. So even a 60% BTE stationary natural gas plant + transmission and charging losses still doing much better with an EV than conventional ICE. And that's before we get into renewables or "low carbon nonrenewable" nuclear which makes it a no-brainer, basically. In commercial aircraft or heavy duty diesel pulling some ridiculous amount of weight across a continent the numbers are much more difficult to make work. I honestly think in 5-10 years we will still be seeing something like the Achates opposed piston diesels in most semi trucks running on a blend of renewable/biodiesel. Applications where the energy density of diesel is just too critical to compromise. CARB is running trials of those engines right now to evaluate in real world drayage ops, probably because they're noticing that the numbers just don't work for electrification unless our plan is to make glorified electric trains with high voltage wires running along every major highway and only a token amount of battery to make it 30 miles or something like that after detaching. Transport emissions is not insignificant especially in the US, but yes there's a lot of industrial processes that also need to be decarbonized. I agree the scale of the problem is pretty insane but EDF managed to generate ~360 TWh from their nuclear reactors last year and this is with decades of underinvestment after the initial big push in the 70s and 80s. I don't think the frame of reference should be solar-limited. France is not exactly a big country either. Maybe it doesn't work everywhere, but it doesn't have to either. We just can't live off of fracking forever and expect things to be ok.

Somehow Vertimass/Oak Ridge National Labs has figured out a catalyst that can convert ethanol into C9-C10 hydrocarbons in basically a single step without ending up with a bunch of ethylene or similar waste products: https://patents.google.com/patent/WO2023224867A1/en I still don't think anything like this will keep us from needing to transition to EVs regardless along with all kinds of other electrification, but things like this will go a long way towards alleviating the problem of how to electrify things like planes. Renewable diesel is seemingly an easier problem as well, Chevron is already running refineries for the stuff and the primary feedstock is tallow and other waste fats from agriculture.

What about renewable diesel and/or gasoline? I see some projects spinning up like de-oxygenating ethanol to make drop-in compatible bio-gasoline especially in CA. I still think the future is EVs and we should've all gone full throttle on nuclear power after the 1973 oil crisis like France. Despite 15 years of work in CA to reduce the CO2 intensity of generation with renewables our electric grid is still far worse than even "low carbon" nuclear power. ICE is pretty cool when you aren't depending on the stupid thing to be practical and reliable and cheap as possible to get you to work every day. It's kind of like mechanical watches or vacuum tube amps.

Reminds me I really need to install that HKS oil cooler I bought years ago.

I just did an oil change on my daily which used oil that is probably 2-3 years old. Normally I try to follow exact viscosities, but my LS400 is fairly tolerant. Dumped something like half a quart of 0W30 Mobil1 ESP X2 in there, followed by 2 quarts Pennzoil 5W30, followed by ~1.2 quarts of liquimoly 5W30 LL04 spec oil. Then the rest was QS euro 5W40 which is actually so thin it's basically a 30 weight oil. All this is to say it doesn't matter that much. We aren't talking about brake fluid. For an RB I would recommend a high ZDDP oil because it doesn't use rollers in the interface between the cam and valve, but a 5W30 or 5W40 is fine to use for street use. The 10W60 guidance really only applies if you're getting it hot and pushing the engine hard.

Yep, looks like some random aftermarket bit that is likely generic as well. Personally I just log everything to a google doc.

You can try shoving a borescope down there to see what's up.

I could see someone trying this to save money on oil changes.

65601-05U00 is the hood latch. 62550-08U31 is the support that holds it to the radiator core support. They are all super discontinued so I don't really have any great leads on how to source this stuff.