GTSBoy

Meh. I knew it would happen. The only question was whether I would have to turn the boost down a little or a lot. The above numbers come from running my controller on LO, which (setup on the original turbo) gave up a couple of psi LESS compared to the HI setting. I had left it on HI for the first test drives, so it must have been exceeding the AFM limit and running close to or perhaps over 100% DC. That is what's scary. At least it didn't get too much of that. It seems a lot softer with the lower boost setting, so....it clearly wants and needs more. Thus... Injectors and AFM upgrade are on the short term plan now. But I have to go away again for a few weeks, so the car will sit.

It's a nozzle used to generate the suction. It's sized to produce enough suction with the stock fuel flow driving it. If you upsize the pump then you have to squeeze that increase through there. And you get LOTS of suction. I don't know how much to drill it out. Remember that cross sectional area increases with the square of diameter, so you probably don't want to drill it out a lot, for "only" a 255L/h pump. You're up about 25-30% on stock capacity, so you probably only need about a 10-15% diameter increase.

Logs showed a few interesting things. I probably shouldn't have leaned on it as hard as I did with old fuel in it, because at other times this week I'm sure I heard an angry little man with a hammer. But anyway....I gave it a bit of curry and found: AFM truly maxing out at 5.1V. Just. Like, it only gets there at the very peak of the logs. It's not clipped at 5.1V at all. Injectors went to over 17ms and reached 86% duty cycle. So, the true limit on the stock stuff is the AFM, if you want to actualy know the load. Peak TP (in Nistune, the load index) was 192. My last column is 208. So....after a new AFM and injectors I have to hope that the total injection multiplier thingo does its job and I don't have to rescale. Neo boost sensor saw 13+ psi during pulls and peaked at >16 psi, probably when I started to close the throttle. CEL is on. Bloody neutral switch has died. Was working until the gearbox came out. Grr. Petrol is enormously expensive atm and I don't want to fill it, but I'm going to have to in a day or so. Then we'll see if it still rattles at odd times.

It's a waste of time. You can;t go back and edit posts after they're a few hours old. You're going to have to ask a mod to paste into it. Ah. I see you worked it out.

There is no 56 in the manual. Perhaps you should take it to a workshop and put a proper diagnostic handset on it to see what that says.

For a single gate on TS manifold/housing I would try to take separate pipes from each side of the divided manifold collector over to the gate and do another merge collector between two into the gate. You make a divider in there that sits right up close to the poppet valve. When the valve is closed you retain decent scroll separation. When the valve is open, it doesn't matter many more anyway. The only hassle is the geometry and space required to build that. It has been done, so it can be done.

There's more than you might think though. Recent learnings from the last month: The Hitachi core is really long. The HG highflow's BB core is really short. So even though the housings are the same as stock, with the turbine housing located in exactly the same place, on the exhaust manifold flange, the compressor housing moves backwards. You have to remake parts of the intake pipe from AFM because the BOV recirc pipe and engine breather come in to suit the forward location. They don't want to move back without even more rework. The turbo heat shielding needs rework. The new oil and water line locations don't work with it. The water lines have to be redone. You can't hope to fit the big Nissan water fittings onto the smaller inlets of the highflow core. This is fine, and expected, as it is written on the webpage. Tao's choice of oil drain adapter that he sends is too short to consider using. Using the shorty would bring the rubber oil drain hose right up close to the turbine housing. We didn't want that, so had to source another. The wastegate actuator bracket doesn't fit (on a Neo in an R32) because it hits the chassis rail. The straight actuator rod places the actuator too far outboard. Need to cut and shut bracket and rod to use the original bent rod from an original Nissan turbo, or fab completely new. None of this is killer, and at least you don't have to do a new dump etc. But I'm just pointing out that even the easy option is not always easy. I would not have been able to get this all done in my driveway, for example. Just too many things to be done. OK, some people would be able to get it done in their driveway - but they have more tools and broken bits in their shed than even I do.

It makes me sad seeing Skylines driving around in the filth and slush of the northern hemisphere and having their undersides turn that disgusting shade of red. The underside of most Australian Skylines (the ones that haven't been abused, anyway) shows no surface rust, no rail rust, no rust on the suspension and steering arms, subframes, etc etc.

My inexperienced, never been there, only-just-bought-a-hypergear-highflow-this-month view on the world is that the 7163 is the perfect turbo for a 25Neo, for street duties at that sort of power level. The whole twin scroll and wastegating thing is.... something to agonise over, I admit.

My boost controller is still setup exactly as before on the stock turbo, keeping the gate shut until about 10 psi and delivering about 12 psi. That setup on the stocker gave boost starting at about 2k and as such there was noticeable extra torque in the 2-3k range. The highflow is really not interested in spooling down that low. When it comes on, around 3k, it starts to build reasonably rapidly. But the while thing is very much more progressive and linear, and I kinda prefer surfing around on the torque in higher gears, in traffic, which is where I drive it the most. But...referring back to the "all sorts of reasons why I can't test it thoroughly right now", some of these are that I did not do the injectors or AFM at the same time, and the dyno is broken, so we could not satisfactorily prove that I am not running out of injector. I did give it a hit in 3rd gear (full throttle out to about 7k) and it feels like it has a fair bit of power up there. Given that I was at ~190rwkW before, and that is close to the max of the stock injectors, there is a solid chance that anything that feels faster in the top end is going to be using a lot more fuel and I therefore would be at some risk of blowing it up. I really shouldn't have even given it that hit. I have to go do some logging in Nistune on the weekend to see if the duty cycle is worrying. In the meantime.... have to be a good boy, short shift and all that. Probably should use the enforced discipline of putting the boost controller on LO too, but that's still ~10 psi and it might still be more air flow than the injectors are good for. I don't want to just turn the boost controller off, because that will leave the gate flapping in the breeze and I'll never get any boost (and only 5 psi). Might be worth a look to see how sad it is, I suppose. It's all a bit compromised right now, and I will no doubt have to go back to the Minister for War and Finance, cap in hand, and ask for permission to upgrade bits that didn't break! Then I'll probably find out the (040) fuel pump is old and weak and can't keep up, and the diff will need to be done again, and so on.

Non-sexy new tailshaft has eradicated the horrible driveline vibes. Non-sexy new clutch has eradicated the horrible clutch specific driveline vibes. Mildly sexy new turbo is..... um.... laggier than I had hoped. Boost onset appears to be very gradual now. There are all sorts of reasons why I can't test it thoroughly right now, so the verdict on that outcome is for the future.

I see 2 pics (3 psi dyno chart and 4" dyno chart) and I think that was all there was to start with.

It's an interesting story. The chapter about running a G35-1050 at 3 psi was a little weird!

I wouldn't worry about that. There would have to be clever suspension shops in the US that could disassemble and service the dampers (with internal parts from MCA if required) if required. But I would put money on the concept of you not needing any such service. Even assuming a generous 10000km/yr mileage, you wouldn't wear them out before the heat death of the universe (read that as petrol costs going to $10/litre).

Just contact MCA. Paying in proper dollars should reduce the pain.

Well, they are just pressed in, so they just get pulled out. You have to twist and wiggle. I am absolutely unclear on what you mean by this. If you want to change the fittings, there are dedicated press in AN fittings that people use expressly for this purpose. Available at most places where people sell this sort of stuff for these sorts of cars/engines/projects. Like Raceworks, EFI Solutions. And eBay. And Aliexpress.

No. Whining is either a gear mesh problem or a bearing problem (depending on the the nature of the whine. One man's whine is another man's some-other-noise).

Good.

Was the gear contact pattern properly set up using engineer's blue? If the assembler cannot categorically state that they did, and perhaps, these days, even show you the evidentiary photos....then diff out, apart, new crush washer, etc etc.

I guess you just have to delete the hard pipes and route hose appropriately.

Yeah, they just didn't have enough processing power, or history/experience, to make a system that was truly fit for purpose.

https://mcasuspension.com/mca-pro-sport-nissan-skyline-r34-gt/ 3 grand Ozzie. About 2K greenbacks, plus freight to the home of the free. I just spent more than that on a clutch and a tailshaft. Coilovers are much more sexy. Spend the money.

Which vendors? Besides which, it has been well known that they are 370cc for about 25 years. All the other values, like 330, are just nonsense numbers on nonsense forums in places where people had no f**king idea about Skylines. Whereas, we've had 25Neos here in Australia since pretty much the year that they were released, and started blowing up the turbos and upgrading the injectors about 3 minutes after that.

All generic cheapo stuff. Acceptable, but not great. You in the states? Surely there is a crowd there that does bespoke coilovers in the same vein as our MCA and Shockworks, and KW, etc, in Europe?

There's nothing here.