joshuaho96

DBW allows for idle control without the AAC valve, cruise control without a lot of extra plumbing, traction control, etc. You can also control transients a little better in theory. I personally don't trust aftermarket ECUs to have good DBW code though, failsafes become much more important with DBW, if the throttle can fail open that's a big problem.

Yeah I'm speaking more to modern downsized turbo engines. They try really hard to silence any and all induction noise unless you modify the car quite a bit.

Diverter valves will make some sound but it's very subtle, if your intake doesn't make a lot of induction noise to begin with it'll be pretty hard to tell.

As a general rule cars are only sold shortly after a rebuild if it has gone wrong in some way. It's often possible the rebuild may not have been done at all, just a claimed rebuild to try and sell the car. You should be extremely suspicious if someone claims a recent rebuild and get a full PPI done, possibly even an oil analysis and cut open the oil filter. A lot of machine shops and engine builders just don't take enough care when doing rebuilds to achieve factory quality. If they can't produce receipts or invoices proving that it was rebuilt by someone who knows what they're doing, you should walk away.

If you store it in Japan until it's 25 years you can import it to the US. Registration in California will require a mostly stock engine, you can have a catback but everything else needs to be stock. Expect to pay 50k USD for emissions compliance, roughly 71k AUD at this time or 5.4M yen due to the requirement for all 1996+ vehicles to have OBD2. After that smog will be every 2 years. Smog will be OBD2 connected with exhaust sniffer testing in neutral. States other than Hawaii and CA will be simple, you will be emissions exempt so you can do whatever you want to the car.

Stock dwell time on the ECU will work with R35 coils if you are running a mostly stock engine or somewhere near it. Dwell time increases only come into play when the spark is getting blown out from excess pressure in the chamber.

Looks like you might have shorted something. It shouldn't be possible to damage the coil drivers like this at stock dwell settings.

I would never recommend a big laggy turbo on a street car.

PowerFC is old and doesn't even have knock control. If you don't notice the blinking light while doing a hard pull it will let you destroy the engine. Even the stock ECU has knock control. If you want something that works with all the factory bits and is properly modern I think the best from what I've seen is the Haltech Elite 2000/2500. Bosch 040 980cc injectors with adapters. NZEFI sells them with the resistor pack eliminator. These are proper Bosch injectors, most aftermarket injectors are not very good, don't faff about and go straight to what the OEMs would use. If you are ok with ~450 whp max then I would go with the -9s, it is achievable with 98 RON/93 AKI gas. Especially if you are building a street car. -9s do not give much in power up at all in the critical 3000 rpm region to -7s, I've seen the dyno charts and it's maybe 5-10 whp. If you want to fix that region you need more displacement and/or VCAM. HKS has an intake side VVT kit, PRP is working on a dual VCAM kit that will really eke out every last bit of response possible from the RB26. For fuel pump selection you need to decide if you want to run E85 or not now. If you want E85: Stock fuel pump wiring only supports 15A max. If you want to run E85 with that much power you need a brushless fuel pump. A brushless fuel pump will be able to sustain much higher flow rates even at high pressures and means that the pump will not wear out faster in the presence of E85. Any brushed pump will wear out faster with E85 vs gasoline, this is a fact of life. Deatschwerks and Fuelab are making brushless pumps that will be available before end of year that will be able to sustain 500 whp within the stock 15A limit. Ti Automotive/Walbro is making a 500 lph brushless pump that will draw 25A like the 450 lph brushed pump but at massively higher flow rates, especially in forced induction applications. For pump gas: Nismo/Tomei 276 lph fuel pump and be done with it. Also, ditch the pods if you still have them. They don't filter as well as the stock airbox and will definitely increase silica content in your oil.

Would be curious to know if anyone has gone the Fuelab 48403/48402 route for an in-tank setup. I have seen that Deatschwerks is releasing a 340 lph brushless pump as well, which ever integrates best into the stock tank + wiring would be an interesting upgrade.

Tuning isn't rocket science. Changing injectors is dead simple, especially if you have the "feature pack" ROM for Nistune that allows for injector scaling without affecting the load scale. Matt seems to be pretty friendly to helping people out with simple jobs like this: http://forum.nistune.com/viewtopic.php?t=2656

I do agree that a healthy dose of skepticism for aftermarket parts is a good thing, I think for a long time the default attitude was that aftermarket everything is best. But if you do your research you can find things that will be an actual upgrade and won't cost you in reliability. The 440cc Bosch injectors were originally designed for OEM applications in the early 2000s which means more stringent emissions requirements and reliability requirements due to longer emissions warranties.

What's wrong with Haltech Elite? It seems to be one of the few ECUs that supports all the weird things that Nissan did with the RB26/ATTESA. And proper long term learning features.

Nistune is literally just a daughterboard on top of the stock ECU that allows you to edit values in memory in real time and read values in memory. Nistune's base map should be the stock ECU map. I would be shocked if it were anything else. I understand your desire to keep things stock to have good street driveability. The best way to do that is to find the most modern, split spray, high atomization injectors that will fit the stock fuel rail + intake with appropriate sizing for your power needs. http://www.nzefi.com/product/nissan-rb-440ccmin-top-feed-direct-fit-fuel-injector-kit/ Something like these Bosch 440ccs will likely have better atomization than stock for better driveability. The factory injectors are old tech and have poor spray pattern + atomization. All you have to do to retune is input the fuel injector data into Nistune with the base map, disable the O2 sensor, and check on the dyno that your AFRs for idle, cruise, and WOT are what you expect. If you just want stock performance you're done after that.

Pretty sure, yes. PWMing a brushed motor is effectively equivalent to a buck converter. I think the goal would be to fit the controller into the stock housing + stock harness though. And uprate the power transistors to handle 70-80A.

Massive thread necro here but has anyone considered doing a complete revamp of the FPCM to use a buck converter instead of just increasing the ground resistance? I figure reducing load on the alternator for other items + no resistor heat dissipation to worry about would be a decent benefit for the 6V/10V modes.

That's some neat info. I have seen cases where aftermarket intakes cause immense amounts of noise on the sensor and all kinds of other issues when not designed with MAF in mind which is why I'm reluctant to blindly have a go at it without any real aero/mech background.

Even with a single AFM I haven't really seen single turbo builds that try to avoid turbulent flow into and out of the AFM, most seem to assume speed density instead which doesn't really struggle with these issues. 4D tuning is basically what I described, a blending of MAP and TPS based on throttle position. As you reach something like 20% throttle you go from a filtered MAP signal to TPS as the primary load source with a blending method to make sure the transition isn't noticeable. MAP sensor with a normal single throttle body setup has lots of intake vacuum so you can clearly see what engine load is doing, I don't dispute that speed density works very well in that application. However with ITBs there's so little vacuum volume that the signal is going to be extremely noisy from the intake valve opening events and because all the cylinders are linked there's a big "vacuum leak" from the other cylinders that makes it really difficult to get good load signal from MAP past small throttle openings. I do wonder if you could make speed density and ITBs work without TPS blending if you had a MAP sensor for each runner and only fed the ECU the lowest pressure of the 6 signals being sampled. That could work even better than AFMs. Banking on WB02 isn't a great strategy IMO, my experience with O2 closed loop is that unless you're within ~5% before O2 fuel trim on the dyno it can cause the ECU to start chasing its own tail. California smog tests thankfully exempt AWD vehicles from the IM240 drive cycle dyno test but RWD/FWD cars can be required to do a proper smog test instead of just revving in neutral at 2500 RPM.

The problem with most single turbo setups is that the intake piping isn’t really figured out very well, AFMs are sensitive to turbulence and reversion so I’m skeptical that a Y-pipe on the turbo inlet as a mount for AFMs and then some pods strapped to that makes for a good AFM signal.

I'm questionable on your statement regarding AFMs vs MAP with ITBs. From what I have seen the resolution of the sensor is for a small portion of the total engine load scale which then requires the remaining portion of the map to be reliant on the throttle position sensor. I just don't buy that throttle position is a reliable load signal, there are way too many factors that can change and throw it off. Admittedly AFMs don't have the best transient response characteristics. The MAP could be used within the range that it works as an accurate load signal but after that the only thing that works would be the throttle position signal anyways.

Ceramic coating can be done on low mount manifolds as well, I've just never seen anyone make a single EFR low mount manifold. There's also the problem of retaining MAFs, which I'd prefer due to the ITBs of the stock engine. Speed density blended with TPS can work but it impacts emissions which is a relevant problem for me.

I think the problem there is more like I've never seen a single turbo build where they targeted a power goal of something like 290-300 kW at the wheels. I believe Hypergear tried with the sst thread but I wasn't too impressed with the results. High mount manifolds that I usually see on single turbo RB26s also greatly increases the amount of heat radiating into the engine bay instead of out the exhaust. Not a fan of the extra volume from exhaust valve to turbine inlet either. It's all relative to though, to me -9s are as big as I'd go. Street manners are a very big deal to me, it's definitely never going to be a V8 but I want the powerband to start as close to 3000 RPM as possible and hold out until ~7000-7500 RPM if I can help it.

The GT-SS might be the best balance, I've noticed the compressor efficiency seems to be better in the expected regime of operation vs R34 N1, but it definitely gives something up in response compared to stock turbos. I waffle regularly on what is the best turbo for a 2.6 street car with driveability as a primary concern.

Are your high flow G1 profile dyno comparisons between stock ceramic vs inconel high flow? I would be very surprised if you've managed to maintain stock response.

-7s are going to just barely break 300kw at the wheels, probably high 200s if you have exhaust restriction/wastegate control isn't ideal. They're a good street turbo though. If you want more power -9s will get you there without too much difference in turbo lag, mostly at that 3000-4000 rpm region where you'll notice the difference back to back.