CowsWithGuns

A final observation. When I did boost leak tests, I would have to rotate the crank to *exactly* a sweet spot, otherwise air would be blasting into the crankcase as fast as I could fill it. Then it would hold quite reasonably. Does this mean anything - I assumed it was normal.

Yeah I think a deep dive into timing is what tuner is taking care of as we speak. Regarding boost leaks, I pressurised to 30 psi and was losing ~1psi per second into the crank case which I believe is normal, especially on a cold engine (all coming out the oil cap). No other external leaks per the soap water test. Tuner also has done a boost leak test during pre-dyno inpsection and was satisfied. Makes sense, but it's only 2-3 years old and this implies it would have been spun or mismatched from factory. Not impossible. I believe the tuner is now 'mechanically' inspecting the timing by looking at where the lobes are pointing when the piston is at the top - or something like that. If it really is just a mismatched turbo, I might cry a bit (a lot). Lots of effort went into this lol. But even then, surely I'd be looking at maybe 270 nose offs rather than 240 flat lines? Matchbot gave me the good news regarding the compressor map. But yes no doubt I was chasing a 7163 - but they were 5.5k AT BEST, whereas I snagged the 7064 for 2.5k within Australia. I pray for a faulty head at this point, that would feel 10x better than wrong turbo selection. 😂 Thank you everyone for your feedback, I will report back when we get somewhere.

Video of first assembly (on tune 1 and 2) Second time I had a second person look at it too... man, it's an interesting one to be sure. Tuner already has his suspicions on the camshafts so I shall let him cook - done a few hundred RB's so I'm in good hands 422917743_6740826062707167_6876251978224887678_n.mp4

What do you mean by 'in the wrong spot'? Just that it's out of time with the timing belt? I've reinstalled the cams twice myself, during rebuild few years ago and in october 2023. Didn't notice a difference before and after taking them out recently. I'm ready to learn I'm a weaponised dickhead and the source of my own misery, give me the good news GTSBoy

Hi all, My R34 GTT has been really weak on power across three (different people) tunes, across three turbo setups, both before and after a moderate engine rebuild. I started with ~180kw on a high flow turbo with a nistune after the rebuild. I made 245kw using a hypergear ATR45 for RB25, Stock manifold, china FMIC, 3" turboback, Link G4X. Naturally my spool was slow with this hefty turbo (GT3582 .63 IWG equivalent afaik). That tuner's explanation for the low power was my terrible intercooler. Dyno chart for reference, see red line: My endeavour to have a low boost threshold with a minimum 280kw (ideally 300+) lead me to install: 6boost with EFR7064 T4 TS 0.92 IWG, 4" dump to 5" high flow cat, 3" straight through catback Plazmaman Pro Cooler, 2.5" piping, 60mm (stock size) bosch e-throttle Here is some pics - I am pleased with how it looks at least I am now getting my car tuned. I received a call that my torque curve craps the bed from 5000 rpm - I consented to further diagnosis. He sent me this, showing my dyno result so far, versus a nearly identical R34GTT they have in the shop to emphasise the issue. Note how I flatline at 5k, whereas the blue lined car with a 3076 turbo flies to the moon and 400+ hp. Tuner says my poor performance is NOT normal - I totally agree and am really getting sick of slow car. Tuner has already tested the following: Good, even compression and leak down test. Very low dump pipe back pressure. No significant pressure difference pre vs post throttle body No 'basic' problems e.g. spark, fuel pressure, base timing etc Tested disabling VCT - only lost low end and midrange with no change up top. Further notes Needs ~30% wastegate duty at moderate RPM to maintain 18psi, and it rockets up to 70% at high rpm to maintain. Turbo speed continues increasing with RPM and I am far from the turbo speed limit. Tuner says the nissan manual recommendations of 0.3mm and 0.5mm for intake and exhaust valve clearance is crap, and I should be looking at 0.3 max on both sides on stock cams. I've read similar things on the forums - is there ANY chance that having 0.5-0.55mm exhaust valve clearance may cause this? His next best guess is confirm that the VCT cam gear isn't damaged and moving 'out of time' without moving the cam. He was honest and admitted he is stumped for now, but has further ideas and would like to sleep on it - I do appreciate the transparency. Alas, further diagnoses will cost me fat stacks as it progresses. Does anyone have any suggestions on what might be the issue here? I suspect an EMAP test may be enlightening, but I have no bungs on my manifold.

Ended up reading the whole book. Excellent read, I have learned many things and can already see mistakes I've done on the current build... I think you must have had a different book in mind however, as there was no test data comparing cone angles - no biggie though! Since it's on topic to the thread though, here are Bell's recommendations for intercooler piping reducers: Anyway, just want to ask if you could recommend some other books that offer good car molestation advice please Edit/continuation: I'm reading the last chapter and noticed this bizarre statement: Also, the exhaust size guidelines imply a 3" pipe is suitable for 700+ bhp. Perhaps adequate but far from optimal I'm sure. Since I started this thread and reading more, I've found plenty of dyno evidence that a larger dump to turbine outlet can gives substantial improvements, e.g. https://www.motortrend.com/how-to/modp-1102-exhaust-test-tech/ I guess it just goes to show even elementary guidelines from a well regarded textbook may not be accurate. I find this very... exhausting.

Haven't heard of these until now. Looks the goods, ty for enlightening me. From reading this thread I think I will run it like so (teeing into the thermo housing rather than adding more stuff with a rad hose adaptor). Seems like a sweet 'guarenteed to work' solution as it utilises all the OEM bleed ports. It's a shame to add more mess to the bay, but better than bleeding these demons. Also means I don't have to take the intake mani off to drill/tap This is a GK swirl pot so if the gods are kind all the fittings will match up too!

Hey all, I'm setting up to go DBW (IACV delete) and the front bleeder is blocking my new intercooler piping (and it's grievously ugly). Wanting to confirm that I am not preparing for grief with these coolant changes. These are the flows as far as I can tell. I am hoping that I can block off all red and blue lines with no issues. Assumptions are: The radiator cap will now be the highest point, eliminating the need for bleeders. I vacuum bleed anyway. The three lines to the intake manifold (green, red, blue) also converge with purple from the head and bugger off out the snout to the radiator. My main concern is that I may be introducing 'air traps' by blocking off the two nipples (lime green circles below) at the top of the intake manifold. I don't understand coolant systems properly yet - will this air eventually fart its way to the radiator? If not, is this of any significance? It's a very small volume but I've had some traumatic coolant experiences and seek assurance Cheers

OK - so be it - time for another spot of shopping to get me some 3"-4" reducers, 90s and all the other sources of joy. Hopefully my bandsaw can handle such a girthy chonk of a pipe... what better way to get peace of mind than to make it BIG! Between your post and a writeup I found from a Garrett engineer on this topic (effectively echoing all your points) the nature of the beast is quite clear - much appreciated! Regarding the CFD, I have heard my equivalent PhD expert at work discuss it and it is rife with places to stumble, fumble, and generally produce colourful stinky garbage. I will not use it to try learn ideal exhaust design 😛

GTSBoy, your engineering knowledge is impressive, thank you for explaining this. To be honest, I didn't consider going for a larger pipe for the dump, as I would be necking down to 3" afterwards (perhaps just before the cat). I have some (many - sorry) followup questions Is a larger dump pipe than the rest of the exhaust desirable purely because the gasses are hotter upstream and more pressurised? What are the specific negative consequences of using an aggressive expansion cone like found 'off the shelf' (e.g. 30-45 degrees)? I assume it's still much better than having no expansion at all even if it promotes turbulence If one is using no expansion (3" turbine outlet to 3" pipe), is there still a benefit to having a straight from the outlet followed by bends (rather than bending immediately out the outlet)? Realistically, is it actually worth spending another few hundred and remaking what I have with 3.5 or 4" piping and an aggressive cone? This is the smallest turbine on the B2 frame so my gut tells me it doesn't really matter... still interesting though! I have an urge to learn a CFD software and have a play with various setups so I could have a quantified reference of changes... on which note, GTSBoy is there any CFD software that's beginner friendly you would recommend? All I played with at uni was 1D modelling (hysys) and you can stick it for cars (and my work). TurboTapin, that's some good intel. If you could fit two gates and a 4" without burning everything, then I must be putting too much weight to my heat concerns.

Hi all, I'm working on installing a 6boost highmount and an EFR7064. Having my first crack at stainless and more intricate exhaust work. I have no idea what I'm doing so 'the best way' is guesswork at the moment. I mocked up a bunch of cuts into a new dump pipe. My aims are to keep the exhaust close to the manifold, and as far from the firewall as possible (might put AC back in the future, also keeps distance from heater hoses and ABS if that ever gets returned). I also wanted to minimize total bends for whatever fractional flow gains I can feel good about. Also, less bends = less surface area to radiate heat into the bay. When looking online most fabricators seemed to take a different approach: pictures I've seen so far show a straight from the turbo, a ~90 down tucked close to the firewall, and then further tucking it along the chassis line (note the ~45 + 45 in reference, instead of another 90) I've drawn on my approach versus reference here: I'm starting to doubt my approach (perhaps theres an issue I will run into later following further assembly), and would like to hear other thoughts on what the 'ideal' dump pipe should be. At the moment I think it would look cleaner if it was following the chassis line... but is there any other reason to run a straight from the turbo then ~90 down?

I've been trying to source an EFR7163 TS for a couple of weeks now (for not $5000+) and it's just non existent. Anyone know what's the deal with this or know any SECRET STASHES of this rare loot?

Following up, the special tool obliterates lifter buckets. I assume this happened because I have heavy duty valve springs. didn't realise how much damage it was doing because... I'm a total idiot. FWIW, I translated the japanese workshop manual page and followed the procedure as described. Also possible that this tool is different in shape to that recommended by Nissan, I had a very difficult time handling it compared to videos on youtube (on toyota engines using a similar tool). Ironically, this forced me to remove the timing belt to pull out this fried bucket- the one thing I wanted to avoid - and it is serving to be as much of a pain in the ass as I expected. In conclusion, I recommend the method in the original post to handle this task. Fortunately I was able to rescue the bucket with some very careful fine sandpaper 'machining'

Downloaded and bought. What a gamechanger, that is awesome!

Ah man this forum is something special. It never occured to me that I could depress the buckets with pliers a conveniently 30+ mm spaced tool. Will probably be heinous with stiffer valve springs but I'll fabricate something and try it out when my new shims arrive (I have reassembled the car). Where do I get my hands on that document? I only have the short 'essential info' R34 manual that is in English - no pictures no joy. GTSBoy I was actually halfway through to lifting the cams until I realised I'll have to dump some coolant and pull my fan shroud at minimum to have any access to the tensioner. Also, I saw a risk that I don't restrain the timing belt to the lower sprocket correctly, which means the radiator and the harmonic balancer are coming out (or even worse - I don't realise it moves on the sprocket). Hell no, no thank you, god forbid, etc. FYI, Precision Shims quoted me ~$12 per shim for 16 and $15 express shipping. Great price compared to the alternatives I saw.

I was looking through old posts and got the impression that you have to remove the camshafts entirely (and hence the timing belt) to replace the shims. Can confirm this is not the case and I saved myself a mountain of f**king around. If you need to measure your bucket shim diameters, you can unbolt the cams but keep them attached to the timing belt so they float up on an angle. You should have enough space to pull out three to four cylinders worth of shims (will have to rebolt cams and rotate to access the other cylinders) using a very strong magnet on a stick and a pick to keep the bucket depressed. Cylinder 1 is a bugger and needs some patience, massage, and masochism. They all sucked and my back hurts. Remember that the very first camshaft retainer needs gasket schmoo on its tips (scrape and reapply), and follow the order of tightening and torque specs in the manual. Similarly, apply sense when unbolting the cams so they do not have excessive bending load applied along their length. Keeping the belt on makes this more difficult and I wouldn't be surprised if it's, strictly speaking, incorrect procedure. But it's an RB so - she'll be right I'm ordering my new shims from Precision Shims in melbourne per another forum members recommendation. Hopefully they aren't $30 each like you find on 'RB25 specific' shims lol!

What am I missing here. It seems the cost of TS IWG 7163 is very similar to say, a vband IWG? The manifolds are the same, the turbo is ~$100 different... are there some other expenses of TS? Mind you it might get pretty expensive (emotionally) if I get pissed off by the choke and/or decide 350kw on E85 is for me 😛 Regarding my goals, I just put 300kw as a reference. I want 10000kw, and I want full boost at 1500 rpm 1 nanosecond after pressing the throttle, don't you?? I'm in a weird place. My current ATR45 build (did it just under a year ago) was tuned by... a 'reputable' tuner who totally shit the bed. Car would stall on clutch ins, my accel enrichment was running the default values, it would run lean (think 1.1 ) on part throttle/cruise at some rpm, and rich (0.9) at other rpms, the VCT was on at around 2000 but my experimenting found I had *way* more torque at 1500 with it on, oh and the knock sensors they installed served only for the ears, and aren't tuned in as a safety... hmm the cold tune sucks too! I sent it back, some of it was improved, so I got mad pissed and taught myself tuning from the HP academy course and fixed the majority of the above. But I'm not game to touch ignition timing or the fuel tables above 3000 rpm. Red line is the results (upgrading from nistune with a very old highflow turbo; blue line). Was verbally told that 240 on this dyno means about 270. Whatever. They told me (I agree) my IATs are insanely high so gonna get a plazmaman as part of this build. The car sucks big balls until 4000 rpm, and then the turbo takes its sweet time to respond in the 3000 to 4500 range. Fun as past 4500. I don't know what is the turbo's fault and what's the tunes fault, all I know is the 240-270 I have on the top end is pleasant enough (more would be good), but I'm there probably 2% of my driving time drive... and getting there takes an eternity. Looking at getting this next tune with the EFR at Brisbane Tuning and Turbo (he also recommended an EFR when I popped in last week, didn't specify housing), so fingers crossed. A wise man would sell this shitbox and get a GR Yaris and be happy. I am not a wise man. We are 4 years in, the car will be respectable eventually, heavens as my witness.

Righto then, it's gonna happen. Mounting to the stock manifold would be a groovy adventure, but I'm enraptured by the thought of twin scroll and I'll deal with whatever bullshit comes (knowing that I've been warned) I don't have an FFP and as much as I'd like to burn more money, I'll find a short (probably R33?) TB and run it around the top. Stock j-pipe gives me the heeby jeebies and I look forward to it's elimination. With it settled on the 7163 T4 TS IWG, the next quest is finding the right manifold. I'm intrigued by this Tonnka creation sold on Goleby's at the moment. It looks really pretty and I'm a broad minded person for exposed stainless. If they agree to make me one ungated for a similar price, I'll risk it and try. There's not one hit on SAU for Tonnka and my search on other communities is ongoing. It's sold by a few reputable stores so - maybe it's good? Will also search for low/mid mount T4 TS and seriously consider it - if it exists. Thanks for sharing all that Kink, I'm confident and excited! Install pending over Christmas holidays, possibly with bonus aircon return lol. I'll post the results here and in the dyno thread.

Thanks for your feedback guys, that is some good food for thought Kinkstaah. I'm still unclear on whether two EWGs are required to do TS setups correctly, or did you and your friend only have one? I don't have AC (although I might reinstall it with some custom lines when I get over the hotboi life) so that's a non issue. Custom intake and exhaust is going to happen regardless, and even with my hypergear 'bolt on' I ended up doing custom oil/water lines because AN is cool. Plumbing EWG is an extra bit of dicking around and cost that I don't welcome (my welding/fabricating skills are poor enough) and I don't really expect to go E85 anytime soon, or ever, unless there's a pump much closer to home. So, with all that said, would IWG still be a hefty restraint on my top end? I was playing with the matchbot and I'm getting ~45% gating depending on assumptions, on the 63mm 0.80 turbine. Seems very high (tech manual does not specify the G-type housing wastegate limits, other housings are between 40-45%). It's a shame my engine is semi built (forged pistons, valve springs and oil fruit) from a more ambitious era and I won't be using its potential. I keep wondering if I should upsize to a 7670 - but then I immediately conclude its foolish because it really is my daily driver and I just am sick of getting slapped by civics at low speeds Unless it isn't foolish??? Truly this is the worst part of cars, decisions like this keep me up at night. I can't find enough (any) dyno comparisons of a 7163 TS to a 7670 TS on 25 NEO to have something quantitative to decide on 😪

Hi guys, hoping I could get an idiot check. I'm running an R34 with a stock manifold, Hypergear ATR45. I find it quite unresponsive for a daily driven street car - no surprise given it's based off a GT3582 .62. I want to shift the power curve as far to the left as I can, whilst maintaining peak ~300wkw on 98. Looks like the best way to achieve this goal is to get an EFR7163 (or 7670 not sure yet) T4 TS IWG. I couldn't find an off the shelf IWG T4 split manifold but I imagine that is zero drama for 6boost or sinco to make. If that's silly and I have to get twin EWGs, then I'll scrap the EFR TS plan to save cost (and probably just go the pulsar). The original plan was to get a Pulsar G30-660 or even a G25-660 on a vband with EWG and save some bucks (and have the perks of EWG) but I'm nervous that the pulsar turbos might underperform a real Garrett. Also it looks like the EFR spool faster and at lower RPMS, especially if twin scrolled. If I was to spend the money on a real Garrett G30 then it makes sense to me to bite the bullet for the EFR. I assume I'm on the right path here but would welcome a smack of wisdom (or a blessing) from ye with experience.

Couldn't edit my post, sharing my discovery here: https://www.leesonengineering.com.au/blog/r200-350zgtr5x1-stub-conversion/ This mob will convert your stubs to accept both 5x1 and 6x1 patterns. With this option available down the track, I'm going to go with the recommended nismo LSD for my car which will come with 5x1. I was considering trying to get something with 6x1 stubs to 'future proof' my drivetrain but couldn't figure out whether the diff centres in those kits would be different or not, risking fitment issues with my diff housing.

I've got the 5x1. The car is lowered a fair bit - I see your point here. No idea, the cars seen a lot of action from the prior owners and lately from me so I guess it's a given eventually it wears out. Regarding the 350z setup. I'm not down to go to the ~3.5 ratios the 350z runs. Currently I'm stock at 4.11, lowest I'd consider is 3.8. Getting a diff setup between 3.8 and 4.1 that accepts 350z axles and has a fully functional LSD (helical or mech) would be the dream. I have more research to do, thanks for your input.

Hello friends, The other day I snapped an axle and have been thinking about upgrading diffs. Spent a few hours trawling through and have settled on upgrading to a nismo 1.5 way for my daily r34 gtt (I have no hopes for finding a nice helical from an s15 or late r34 any time soon, and if I'm gonna spend 1k+ on a centre it might as well be the 'best' one). Naturally I could go with 38420-RSS15-B5, the default for the r34 gtt, however; since my axle has snapped and I haven't sourced a replacement yet (seeing them $600+ second hand - gross!), I was wondering if theres a particular stub axle with readily available/cheap axles from newer nissans (e.g. 350Z) that are as strong or stronger than the stock r34 ones. This option has broadly complicated things as I wouldn't know where to begin with determining what shafts have what bolt patterns/lengths to fit my car, so I was hoping someone has some pre-existing knowledge to share. While I'm at it, it's a mystery my axle broke spontaneously (admittedly during a pull). The road was wet, and I only only push 230kw at the moment - any reasons why it might just give up and die like that with my relatively weak car and poor traction conditions?

Gday SAU, On my R34 sedan, the doors love to close shut on their own, and are prone to swinging wide open on a windy day. During my search I've learned about the R35 door link upgrade, however; people have only done this to coupe R34s and S15s as far as I can find. The Nissan EPC has told me that the sedan and coupe have different door links, so I'm not game to buy an R35 set on the (wishful) chance it works for sedans. Has anyone found a clean solution to this problem, or tried the R35 links in a sedan?

Firstly big respect for your writeup, however; I just had an experience that contradicts this. TLDR: Gray/Red exists and affects the dash lights and the switches, however; I ended up not using it at all as it was not needed and caused new issues. Replace Gray/Red with the Gray 12V constant power and above advice worked! I got the car with auto to manual conversion already performed - it had reverse lights pretty sure, but they stopped working at some point. Never had neutral switch, never had the auto cluster light up with P, N, or R. My setup: R34 GTT with R34 box, auto cluster, auto ECU, nistune with a MANUAL base map. Symptoms of no neutral switch are questionable idle AFR's that seemingly cant be tuned out. The original wiring: Inhibitor (Black/Pink) with constant 12V power (Gray) joined together (correct) Neutral switch: Green/White (correct) and Yellow/Brown (seemingly incorrect) Reverse switch: Red (correct) and Black (shared with Speed sensor, presumed earth I forgot if it is, seemingly incorrect, HOWEVER IT WORKED AT SOME POINT - my flimsy guess is changing the base tune map from an auto to a manual caused this). This wiring as I found it is exactly as directed by a guide on SkylineOwners that always shows up top of google. It does work for some people - seems to require a manual cluster? I found the Gray/Red wire and it blew the A/T fuse once I connected it to enough things. I experimented with countless combinations and at one point I had constant neutral, constant park, and in reverse all three (with lights on). There was another combination that caused the dash to show neutral OFF, but the ECU was reading neutral ON in all gears. After enough trial and error, I found the pattern and my new wiring that works perfectly (Never shows P, N in neutral, R in reverse, ECU reads neutral position correctly too; reverse lights on when desired, speedo works). GRAY 12V power to Inhibitor (BLACK/PINK) GRAY 12V power also to reverse switch, other wire RED GRAY 12V power also to neutral switch, other wire GREEN/WHITE This was the mightiest clusterf**k to figure out (the loom has been absolutely mangled with random colours everywhere changing up along its length with splices) but we got there! I think previous owner had a bad time of it and gave up lol. Please let me know if there absolutely is a purpose to the Gray/Red wire regardless of the fact my setup seems to work now