joshuaho96

Not sure why but RBF660/700 or Castrol SRF is listed as DOT4, not 5.1.

This has clearly gone off on quite a tangent but the suggestion was "go standalone because you probably aren't going to stop at just exhaust + a mild tune and manual boost controller", not "buy a standalone purely for a boost controller". If the scope does in fact stop creeping at an EBC then sure, buy an EVC7 or Profec or whatever else people like to run and stop there. And I have yet to see any kind of aftermarket boost control that is more complicated than a PID controller with some accounting for edge cases. Control system theory is an incredibly vast field yet somehow we always end up back at some variant of a PID controller, maybe with some work done to linearize things. I have done quite a lot, but I don't care to indulge in those pissing matches, hence posting primary sources. I deal with people quite frequently that scream and shout about how their opinion matters more because they've shipped more x or y, it doesn't change the reality of the data they're trying to disagree with. Arguing that the source material is wrong is an entirely separate point and while my experience obviously doesn't matter here I've rarely seen factory service manuals be incorrect about something. It's not some random poorly documented internal software tool that is constantly being patched to barely work. It's also not that hard to just read the Japanese and double check translations either. Especially in automotive parts most of it is loanwords anyways.

How complicated is PID boost control? To me it really doesn't seem that difficult. I'm not disputing the core assertion (specialization can be better than general purpose solutions), I'm just saying we're 30+ years removed from the days when transistor budgets were in the thousands and we had to hem and haw about whether there's enough ECC DRAM or enough clock cycles or the interrupt handler can respond fast enough to handle another task. I really struggle to see how a Greddy Profec or an HKS EVC7 or whatever else is somehow a far superior solution to what you get in a Haltech Nexus/Elite ECU. I don't see OEMs spending time on dedicated boost control modules in any car I've ever touched. Is there value to separating out a motor controller or engine controller vs an infotainment module? Of course, those are two completely different tasks with highly divergent requirements. The reason why I cite data sheets, service manuals, etc is because as you have clearly suggested I don't know what I'm doing, can't learn how to do anything correctly, and have never actually done anything myself. So when I do offer advice to people I like to use sources that are not just based off of taking my word for it and can be independently verified by others so it's not just my misinterpretation of a primary source.

I don't really understand because clearly it's possible. The factory ECU is running on like a 4 MHz 16-bit processor. Modern GDI ECUs have like 200 MHz superscalar cores with floating point units too. The Haltech Nexus has two 240 MHz CPU cores. The Elite 2500 is a single 80 MHz core. Surely 20x the compute means adding some PID boost control logic isn't that complicated. I'm not saying clock speed is everything, but the requirements to add boost control to a port injection 6 cylinder ECU are really not that difficult. More I/O, more interrupt handlers, more working memory, etc isn't that crazy to figure out. SpaceX if anything shows just how far you can get arguably doing things the "wrong" way, ie x86 COTS running C++ on Linux. That is about as far away from the "correct" architecture as it gets for a real time system, but it works anyways.

I'm saying if you spend some time wiring in an ethanol content sensor then it works like OEM and you don't have to plan your life around sourcing E85 of the right concentration or worrying about flashing between tunes. I would agree with the logic of "it's cheaper to pay upfront for flex fuel vs potentially an engine rebuild", especially on something like an M2. This is a good point but I could never get my Skyline insured with comprehensive coverage if it was a daily.

76884-AA135, looks like Nissan's EPC calls it a rear pillar inner insulator: https://www.amayama.com/en/genuine-catalogs/epc/nissan-japan/skyline/bnr34/6628-rb26dett/body/767?frame_no=BNR34-000000

Not wrong, but if I expected to not drive the car for a while but do a fair amount of garage shuffling I wouldn't run E85. Flashing a tune every time that happens sounds like a headache compared to a single map + flex fuel sensor.

Yeah, but in the US if you do this it's almost guaranteed you get the infamous black goo buildup in intake ports and E85 fuel stations while relatively common are nowhere near as readily available as E10 premium unleaded. E85 is also not regulated that well out here. Lots of places "E85" is actually as low as E50 in the winter to reduce cold start unburned fuel emissions. E85 especially doesn't do well with short trips, Mike Kojima at MotoIQ documented how his daughter's EJ25 running E85 experienced stuck rings from being driven short distances and the crankcase was filled with a thin layer of condensation + oil emulsion as well despite very aggressive oil change intervals.

I would never run E85 without an ethanol content sensor. Just not worth the headache. Having to reflash the tune and only refill the tank when it's very nearly empty is super annoying.

High ethanol concentrations all the time is bad for the fuel system. Not because ethanol has some inherent issue assuming you've done your fuel system setup correctly, but because PIB isn't soluble in ethanol and it contaminates the entire supply of fuel in practice. It is soluble in gasoline so you want to run a tank of normal pump gas every so often to flush all of that out before it causes an injector or something to clog.

I really find it hard to believe that boost control demands enough compute that it needs its own module. Especially if the only real logic is closed loop boost control + adjustable boost target based on a dial or ethanol content.

Isn't the whole point of this integrated circuit thing to put a bunch of hardware all in one little package? Integration also brings its own benefits, at least in theory. If you were to put an electronic wastegate or do an N54-style vacuum wastegate that is normally fully open but closes under vacuum integrating everything allows you to do tricks like full wastegate bypass at cold start to warm the cats or in eco-mode under a certain torque request to reduce exhaust pumping resistance. Or full bypass as a limp mode if a certain amount of knock is detected. Or managing the compressor so it never reaches the surge point. None of this is strictly necessary per se but standalones generally have good enough boost control. PID control isn't exactly some crazy difficult problem to solve.

10 years is really pushing it. At 7-8 years you need to inspect frequently for signs of dry rot.

Yeah, it's more a personal pet peeve. I would rather go standalone purely to avoid putting in a Profec or whatever other standalone EBC.

I would not replace the gauges. A well setup tune should never require any of that. I'm of the opinion that if you can't safely hand over a car to your parents to drive it's not fit for purpose and more engineering work should be done. Honestly I'm not a fan of external boost controller boxes either but if you have to you can shove the controller into the glovebox or something once it's set up. Tee it off the OEM MAP sensor. Also you probably want to put a two pin plug on the new solenoid, bolting it to the OEM location works. Just separate the wastegate line and compressor outlet so it will work on a 3 port solenoid, kevboost was walked through how to do this on an RB26, same idea just different locations on an RB25. You may have to remove the restrictor in the OEM hoses if they're still in there.

This piece is obscenely discontinued. I honestly hate the frameless window design because the rubber gets stressed and the guides as well every time you open and close the door.

This would be a new pump with new gears. I'm just unclear on whether it's a good idea to run more oil pump flow if you don't actually need said flow. Oil level is set a minute or so after shutting off a warm engine so wouldn't the high RPM oil level in the sump end up lower all things equal? Plan is OEM clearances, main concern in my mind is whether the OEM pump can keep up with the flow requirements of any additional oil coolers.

Right, but if you replace the pump gears + put a spline or sine drive gear on the crank on a Nismo/OEM/N1/etc pump at that point do you really still want more flow/oil pressure? Let's say this is a the aforementioned "keep it simple" build, no more than ~400 kW at the crank.

I really don't understand the point of aftermarket oil pumps if your particular engine doesn't need more oil pressure. As far as I can make sense of it the problem seems to be cavitation from sucking air, maybe the pump gear design with how it interfaces with the OEM crank, and maybe the backing plate screws wanting to loosen themselves. How does flowing more oil fix these issues?

Save yourself the headache of an alarm. Immobilizer on the signal side of the main EFI relays so it won't start is good enough. DIY killswitch is the same thing except instead of a nice passive system you need to remember to switch it on and off.

Yeah if the goal is to drive something then modifying a car is a bad idea.

Is it just me or are those injector ms values insane? I swear from staring at Consult logs it's nowhere near that on factory 440cc much less 980cc.

For a daily just run Akebono ceramic pads. That's what they're optimized for. Obviously don't try to run it on track or anything like that.

OBD1 is a catch-all term for pre-OBD2 which could have basically any connector design and protocol. I really don't understand this attitude against using data logging for issues that can be multi-causal and subtle. A no-start situation or something like that sure the scan tool does nothing but if it runs like shit it can often be a sensor issue. When a friend of mine reliably had issues with his N54 not able to stay running eventually I narrowed down the issue to a faulty fuel pressure sensor. Only way I could do that was a scan tool to look at the fuel rail pressure and see shadow codes for fuel pressure. Then check against a pressure gauge. Is reflexively firing up the data logger probably a bad habit? I guess, it can encourage people to not listen/observe but on these old OBD1 cars just taking a log really doesn't do anything by itself. You still have to synthesize everything you know and think about what it all means.

Breather for it. If it's anything like the GTRs it should run up to the top of a bellhousing bolt.