joshuaho96

Has anyone actually done a BSFC map of the RB26? I'm sure it's going to be ugly but curious to know what the ideal operating points are.

Sometimes the oxidation/cracking is on the inside of the lens for whatever reason. If that happens it's easier to just replace the lens with new if possible.

Doesn't Behrman make a kit to fix those? Or is it only for the GT-R trims?

I would go look up the LS2 coilpack recommended voltage vs dwell time spec. Then if you know the base dwell time for a given voltage then you can convert from the raw 0-255 values to milliseconds.

I would check when you can in Nistune to see the AAC Valve live value at warm idle, make sure you have some range both above and below or you might have idle issues. As the documentation suggests you want to change the dwell vs voltage values and not much else. In theory you could probably leave them stock but you won't realize the benefit from them.

Generally speaking you should only adjust the idle adjustment screw if you have Consult readout to log the AAC valve duty cycle. I believe recommended target is 35-40% in warm idle.

The ECU sets the idle target. If you haven't disabled this function in consult the ECU will be fighting you the whole way. The manual spec is 950 so it will open up the AAC and adjust timing to get to 950 rpm.

Any more than 15-20% is cause for concern. If the engine is still being broken in the rings might not seal very well but afterwards it should be 10% or less when the engine is warmed up.

I'm aware of the Midori sensor, they have more info here: http://midoriseibi.co.jp/tuning/r34/yaw-rate-sensor.html If you read the link that I put up it says this: Odd. These pages are out of the R34 GT-R Service Manual supplement. I know what I have seen on R34's. I am not aware of an early and late change, as you can see here - Yaw rate is part of HICAS. No Yaw rate in the ATTESA ETS- PRO system.

Definitely a bit of a tangent but still interesting. My source is here: https://www.gtr.co.uk/threads/handling-differences-due-to-mechanical-vs-a-lsd-r33-r34-gtr.176499/page-2 If you have some proof that the yaw sensor in question does in fact connect to the ATTESA system for A-LSD control I would be interested to learn more.

There's only two good explanations. Either they were thinking of compression tests when they said that or they're not actually as reputable as you say they are.

I was under the impression that the yaw sensor on the R34 is actually for HICAS, not the A-LSD.

I wouldn't decat a street car which is what I assume you have if you're concerned about dB limits. Decatted cars are obnoxious to be behind.

Most of them do look pretty flat but one of them looked a little suspect, I couldn't tell if it was just the lighting or something else. I do agree the TR14 connections look pretty nasty.

The photos aren't super useful unless you are taking macro shots of each capacitor in good lighting. The tops of the capacitors should all be perfectly flat. If you see any bulging replace all the capacitors as a preventative measure. You could meticulously check the resistance of each solder joint to see if you have a bad joint somewhere.

If you got water into the electronics you won't be able to repair it most likely. You can try cleaning the corrosion off the board but usually the corrosion etches away critical connections.

Another thing to consider is capacitor rot on the ATTESA-ETS control unit. Crack open the controller and inspect visually and nasally. If you can smell ammonia you have some bad electrolytic capacitors. If you can see bulging or leaks on any of the capacitors you need to replace them. Pretty much every one of these 90s cars is due for new capacitors in pretty much every board after 25-30 years if they've been driven regularly.

https://www.shell.com/business-customers/aviation/aeroshell/knowledge-centre/technical-talk/techart-18-30071600.html Gasoline went unleaded in the 70s, no reason to look back. Arizona E85 may be inconsistent but it's nothing a flex fuel sensor can't deal with. Ethanol blends vary between E30 and E85 at the pump depending upon season as ethanol doesn't want to start in the cold and evaporative emissions are harder to control. Leaded gas is nasty stuff. Lead is a potent neurotoxin and when you burn leaded gas it's being spewed into the air in a form that is easy for the body to intake. There is a lot of research out there that strongly correlated a crime spike in the 1970s and 80s to leaded gasoline. General aviation is the only major consumer of leaded gasoline at this point and it's only because the engines they run were originally certified on leaded gasoline and the aviation industry is extremely conservative. They still use magnetos and carbs. An RB26 is designed to run unleaded fuel and not designed for leaded fuel at all. So why bother with the thing that's more expensive than ethanol mixed with mogas when lead poisoning is a real risk and lead could damage the engine in unexpected ways?

I wouldn't run 100LL on any reasonably modern car engine. Even if you decat the O2 sensors will foul, the lead oxides will foul up and corrode exhaust valves and spark plugs. Just way too much effort for an especially toxic blend of gas when E85 is cheap and is comparable. Water/meth is complicated but if you're willing to spend a lot of time and effort on making it work then it's great too.

91 AKI Canadian is equivalent to 95 RON. 93 AKI is equivalent to 98 RON as you have suspected. I believe that 91 octane in Arizona, California, and Nevada is so exceptionally bad that many tuners have special maps to dial back the timing if you plan on using gas in those states.

Water meth injection is no joke to implement. If you’re serious about I would either try to figure out how to source the Bosch system or Aquamist. Port injection should be used if you want to spray a lot as the OEM plenum and runners are not designed to ensure equal distribution of liquids for each cylinder. The post IC spray flow has to be pretty low to make sure it vaporizes before it hits the plenum. In small amounts it’s probably fine because it’ll go towards cylinder 6 but too much and the AFRs will be uneven. Also make sure to get a tank that is properly baffled with a flow sensor of some kind to verify delivery. I would also integrate control into the ECU.

The easy way would be to link a kit for a low mount single that is bolt-on and keeps all the things I’m asking for. I’m not exactly chasing after performance here either. The M4 has dead steering, sounds pretty terrible, and is kind of a pain to see out the front due to the tall hood from the charge cooler and pedestrian safety regulations. I also want the driving dynamics of ATTESA-ETS. It is extremely competent technically though. Yeah I'm a big dumb American. I don't know enough about this stuff to attempt to make a single turbo conversion from scratch. I think the BMW S55 engine does have more advanced control systems but at the end of the day it's a parallel twin turbo setup like the RB26. They have neat tricks to play like fully electronic wastegates and soon 48V mild hybrid but the core architectural trade-off between a bigger single and small twins is still there. I suspect it's really a packaging, thermal management, and emissions problem for BMW but that's just me armchair engineering.

I'm aware it's been done for a while now, just not in the form I'm looking for. Not interested in high mount, low mount manifolds are few and far between and generally not recommended, I would really want a cast manifold for longevity reasons, bolt-on kit with heat shields, piping, etc all ready to go with a proper airbox/paper filter/snorkel for cold air intake. I don't think I've seen a single single turbo conversion that actually looks like what I'm interested in. Also, the HKS GT3-SS really helps with low-end spool and mid-range for a mostly stock car, based on the dyno curves I've seen. The cost benefit analysis doesn't necessarily make sense per se but frankly if I were buying based on performance per dollar I would get a Corvette.

The headache is in validating that the thing will fit correctly, won't crack/corrode, that the oil lines and water lines for the turbo are properly routed and won't fail 50-60k miles down the road, that the intake is properly designed to not suck rain into the engine, properly mounted, has appropriate flow characteristics without weird resonances, can fit a MAF without a bunch of signal noise if ITBs are retained, and all the unknown unknowns that come with trying to make significant changes to the intake and exhaust of a turbo car without the experience or knowledge of what works and what doesn't. I just don't see a convincing case for spending a lot of money on a single turbo conversion when the power goals are conservative and the primary interest is in a reliable street car. The goal is to drive the thing, not to keep it in the garage as a permanent project.

I'm aware that it's a DI motor with VVT + VVL and a number of other changes. My point is that even now when BMW has the option to ship a single turbo for an I6 in their 500 hp+ models they elect to continue with twin mono-scroll turbos instead. Clearly it's not as cut and dry as is being claimed by Andrew Hawkins et al. The RB26 turbo shuffle is a problem but isn't intractable, it seems like much of the problem is related to the twin turbo pipe and the near 90 degree merge. I don't think that alone really justifies the expense and headache of figuring out how to retrofit a single turbo to a motor that never shipped in that configuration.