nouveau_poor

Absolutely could be. I collected data logs from when the O2 sensor was still out and also after I had replaced it so will try to compare them. Pretty confident that the affect is lowered with the new sensor, will check logs at the same RPMs/conditions.

Update: O2 sensor in my downpipe turned out to be faulty when I plugged in to the Haltech software. Was getting a "open circuit" warning. Tons of carbon buildup on it, probably from when I was running rich for a while before getting it corrected. Replaced with new unit and test drove again. The shuffle still happens, albeit far less now. I am not able to replicate it as reliably and it no longer happens at the same RPM levels as before. The only time I was able to hear it was in 5th going uphill and another time in 5th where there was no noticeable incline but applying more throttle first sped it up and then cleared it. Then once in 4th when I slightly lifted the throttle going over a bump but cleared right after. My understanding is that with the O2 sensor out, the ECU relies entirely on the MAP tune and isn't able to make its small adjustments based on the sensors reading. All in all, a big improvement, though not the silver bullet. Will try validating the actuators are set up correctly, and potentially setting up shop time to tune the boost controller on closed loop rather than the open loop it is set to now. Think if it's set up on closed loop to take the O2 reading, that should deal with these last bits. Will try to update again as I go.

Makes sense. For actuators, if the pressure itself isn't adjustable, that would mean I'd need to think about 2 different actuators with 2 different pressures on paper in order for them to work at the same time if the turbos behave differently. So measure the difference in psi needed to move both, and then get an actuator to match that difference. Assuming I cant get rid of it by adjusting the arms. You're exactly right, never happens in gear 1 or 2. I can occasionally get it in gear 3 if going uphill but its very small. Only ever in 4 and 5. Seems kind of backwards that one of the points of VCAM is faster spool but if it introduces shuffle then it actually slows spool down.

I certainly fall into the annoyed camp, but glad to hear that if it's happening at low boost then I'm not likely going to blow a turbo and end up with metal shards in my oil. Just feels like it prevents me from really driving it without hesitation and "peak" performance. Wonder if it's the VCAM, it did an impressive job of shifting the torque curve and faster spool, but maybe now it's "too fast" and there's too much air for how open the throttle is. Based on some other threads, will also do some reading on synchronizing the actuators. They are the default actuators that come on the Garrett's and I would think they would be set the same coming from the factory, but if the turbos don't actually work exactly the same way at the same time as previously mentioned, it would be worth making sure the actuators are actuating together properly

I appreciate the detailed explanation, think I understand now. I spent the better part of last night reading what I could about shuffle and potential solutions. I had replaced the OEM twin turbo pipe with an alternate Y pipe that is separated further away from the turbo. The current one is from HKS and I had a previous pipe that was separated even further away, both have shuffle. I had heard that a divider can be welded in to the OEM pipe to remove turbulence, and figure that aftermarket pipes that are more separated would achieve the same thing. From what I read, most people with -10 turbos get shuffle due to their size, though it's a bit less common with -5s on a standard RB26. I think Nismoid mentioned somewhere it's because OEM recirculation piping is common in Australia with -5 cars. It seems that the recommendation tends to vary between a few options, which I've ordered in what I think is most feasible for me: 1. Retune the MAP or boost controller to try to eliminate shuffle 2. Install OEM recirculation piping 3. Something called a 'balance pipe' welded onto the exhaust manifolds. I don't know if kits for this are available, seems like pure fabrication work 4. simply go single turbo My current layout is as follows: Garrett 2860 -5s HKS Racing Suction intake MAF delete pipes HKS racing chamber intake piping hard intercooler piping, ARC intercooler HKS SSQV BOV and pipe Haltech 2500 elite ECU and boost solenoid/controller HPI dump pipes OEM exhaust manifolds HKS VCAM step 1 and supporting head modifications Built 2.6 bottom end All OEM recirculation piping was removed, relevant areas sealed off I'll keep an eye out for any alternative solutions but can get started with this. Only other question is, does shuffle harm the turbo (or anything else)? It seems like some people say your turbo shafts will explode because of the opposing forces after a while and others say they just live with it and adjust their pedal foot accordingly.

Thanks for the quick reply. To be clear, when you say turbo shuffle do you mean turbo flutter "stustustu" or referring to something else? I had thought they were the same thing. When I wrote the post my intention was to say it wasn't a flutter/compression surge sound. My understanding was that a flutter sound would be occurring when throttle is released, whereas I can keep the throttle in the same position for this noise

Hi everyone, I've been wrestling with this for a while now and have been trying to find out the cause. For context, the turbos used are Garrett 2860 -5s, the BOV is a BNR32 HKS SSQV IV kit, the car is currently tuned to ~470 whp on 17.5 psi. The car drives normally, pulls well when it doesn't happen, and I can replicate it fairly easily. It does not sound like turbo shuffle or flutter. The engine has only a thousand or so miles and has had this behavior since it was completed. After my engine was built for my R32 GTR, I noticed that the car now sometimes makes an air discharge sound on what appears to be positive boost pressure that sounds really similar to a BOV. I had thought that it was a BOV issue but even when replacing it with a brand new unit, the sound persisted. It seems like it's coming from the passenger side but I may be mistaken. The closest scenario I could find was this post here https://www.gtr.co.uk/threads/maybe-a-boost-leak-opinions.147955/https://www.gtr.co.uk/threads/maybe-a-boost-leak-opinions.147955/ started by @yakshii and it sounds very similar. As in, at partial throttle once I reach positive boost I begin to hear the same psh psh psh psh psh sound like air is leaking somewhere when I keep the throttle in the same position. It most commonly happens in 4th gear at around 3-3.5k RPM and 5th gear around 2.5-3k RPM, which seems to coincide with normal positive boost thresholds. It might be similar to what @Austrian GTR mentioned about his own HKS SSQV. Notable difference would be that when he applies more throttle when it happens, it stops. In my scenario if I apply more throttle during this repeated psh psh psh sound, the cadence of the sound gets faster and louder rather than stopping. If I lift off slightly and apply throttle again, it will normally stop and pull without issue. I've checked all rubber couplers to ensure that they are tight, but have not gotten the opportunity to properly do a pressurized boost leak test. If anyone has had similar experiences or thoughts on what might be the cause, I'd be very keen to hear them. I also have a video of it happening from inside the cabin, if that would make it easier to understand: https://youtu.be/2zqZXcx8jbA

Got them in the other day. I can confirm the r33/r34 nozzles (B8K30-AA000) are the exact same. Hope this helps anyone else that comes looking for it

Got the R33 nozzles on order atm. I'm fairly certain the only difference in parts numbers is because the factory units are painted to match the body and after the R32 they were just black plastic. Should be fine!

Hi all, Bit of an odd question but the only OEM washer nozzles I can find readily available are listed as fitting the R33/R34 models. The R32 (shown below) has it's versions sold as a LH and RH piece while the R33/R34 nozzles are sold as a set (part number B8K30-AA000). Has anyone tried using these nozzles on their R32 Skyline hood? Do they fit without issues or with slight shaving, or are they completely incompatible? Visually they look almost exactly the same as the original factory nozzles I have now. They aren't expensive so I can eat the $30 or so that it would cost to try but I figured I'd ask in case someone had tried it already. Thanks!

I've seen people with success using Simple Green cleaner and a light abrasive like steel wool or scotch brite pad

Dang, wonder how that works out with the tuner. Do they fund a new engine or a different way to make it square?

That's wild. Good that you caught them. And here I am in the states barely locking my doors in the small town I'm living in now. A bad habit I'll have to work on fixing

I think I've read in another thread that one of the best "simple" changes to the engine one can do is to tune some adjustable cam gears and that even on factory camshafts a gear tune can give additional power. Maybe there is a compare and contrast thread out there for the same engine setup. One with factory gears/cams, one with adjusted gears/factory cams, one with one with adjusted gears/aftermarket drop in cams.

Yeah, more searching around was enough to spook me away from them even if the full details about their relationship isn't completely clear. The discount is huge but maybe the above is the reason why, now that I think about it. Not keen on risking an ill fitting cam, or worse a snapped one. Will check out the Kelfords. Any strong opinions on similar spec HKS cams? Seem to be close in pricepoint and I've been very pleased with the other parts they produce.

Finished reading around a bit. So with the official announcement was in 2019, anyone know when Tomei JP stopped supplying cams to Tomei USA from Japan or if Tomei USA has always made their own cams? Definitely going to dig further

Thanks for the feedback both. Reason I ask is that they seem to be a popular modest cam to pair with Garrett -5 turbos, where I'm shooting for the 450-500hp range. An opportunity came up where I could get them BNIB off somebody going a different direction with their build for about 1/3 the normal retail price. Really has me eying them. I'll read through the TomeiUSA forum post that was provided

Hey all, Was looking to get some cams for my R32 GTR and noticed that the popular Tomei Poncam Type B's seem to have two different versions between the USA and Japan. From Tomei USA's site, for part TA301A-NS05C, the duration is 262 with 9.15mm lift. On the Japanese sites like Nengun or RHDJapan the duration is 260 with 9.15mm lift. Is there different versions between USA and JP spec? I don't think it's a typo since the different US suppliers I check have the same information. Both parts are part number 143005. RHDJapan has them for comparable prices to US suppliers, but Nengun lists them for almost 40,000 yen (400$) more, adding more to my confusion. I wouldn't think that a difference of 2 in duration would make all that much difference but am more concerned about possible differences in materials or manufacturing process. Can anyone shed any light on this? Thank you

This might be an obscure piece of trivia, but does anyone know the significance or meaning behind the number 913 on the Impul Momo steering wheel series (Special, Expert, etc.)? The same model that was used on Calsonic race cars at the time such as the Calsonic R32 GTR. I cannot for the life of me find the answer on google or the forum.

The issue in the end was that the speedometer itself, the one with the mileage counter, that was fitted was meant for a late model cluster, rather than the early model needed for my 1990. Essentially, the cable from the ECU that connects to the speedo had nothing to connect to or read, hence no speed reading and resulting in the HICAS light. The continuity from the ECU to the speedo plug came back fine, no wire degradation. From what I remember, I think the actual speed sensor wire was green and yellow if that helps. Early model speedos have this extra wiring bit:

Front end could use some work, the grilles of previous renders looked better in my opinion. Looks fantastic from the inside and side view. The rear I have mixed feelings about, the lights themselves are neat but the black bar they are on looks a bit out of place. I might be nit-picking, but the rear badge also appears very large but it might be my imagination. Maybe it'll grow on me.

Americans will pay unholy amounts for an R34. Whether the over inflation is from Fast and Furious, Need for Speed, or something else, there is no question that the buyers have quite a lot of disposable income. These cars are status symbols at this point. Those who bought theirs before the prices went moonshot really are lucky.

fair enough sure, but why get rid of the timer if he's already got it? The other post sounded like the timer itself would cause an issue.

Why get rid of the turbo timer? I thought they were a good thing for turbo engines to let them sit for a bit after driving before shutting off the engine.