Kinkstaah

This is not what I said. What I said was, any shop. ANY TUNER, EVER, is only going to get your tune dialled into like 80% of how nice it can be. This is not a knock against tuners. This is just because there's only so well you can dial a car in in a couple of hours on a dyno. You (and they, and anyone) needs TIME and lots of it, to really dial in a car. People are not going to pay 200+ hours of dyno time to fully tune a car. But your labor is free. In any scenario, you would get a tuner to do the baseline stuff, and tune the car. You can learn and refine it, to patch up the little gaps that WILL be in there, because tuners cannot predict the future, which is exactly what GTSBoy is saying. Having things like Wideband O2 control is a very useful training tool where as something like Nistune is a more 'basic' ECU, but that doesn't necessarily mean it's better/easier to learn on. You have much less safeties in it too. You get tuning wrong, you can destroy your motor in seconds.

I hate to be that guy, but a highflow that doesn't need a change of downpipes (i.e you need to buy the HPI downpipe or similar, which is good) And 98? Just.... be happy with 270kw. Unless you want E85 which for a daily is something you'll probably CBF running the gamut on in 2024. Just hyper expensive and limited in practicality. All the over 300kw setups are running E85, or external gates. You can imagine E85+External Gate changes things a lot. You can run gates off the stock manifold, or the stock turbo housing even... but you start getting into the "Why don't I just run a different manifold" discussion pretty fast. The LINK ECU is the goods. They fill a similar niche as the Haltech but haven't quite generated their own tax yet. The benefits over a Nistune are really notable if you want to be a tinkerer - there's a lot of custom stuff that goes on in cars like these when you change stuff. A tuner with nistune is good, but you really need tons of cycles and driving around, and different weather and all these circumstances that a dyno just can't dial in. The link will help you do that and get modified cars driving like factory cars.

The blitz does require cutting on the front reo to actually fit the thing. Sadly I had to. Any intercooler can "Support" 300kw. The issue is how much it dissipates the heat. I'm yet to really see any back to back where someone will do say, 30 continuous pulls and then compare the heatsoak between the different intercooler setups, which is what an intercooler is really for. It heavily depends on your use case to determine which one is going to work. Typically speaking though you can't really go too big, or have too much cooling, so everyone generally fills the gap with the biggest thing possible (in terms of the actual intercooler core).

Ye, _how_ did you travel those 109km? I mean if you're doing a track day on E85, 109km is something like three full tanks of fuel Without data logs, can't say anything. Without the ability to change the tune, can't say anything either, you either have a huge leak, a very rich tune, or a very heavy foot or a combination of all of those.

Kind reminder that BMW IS ORDERS OF MAGNITUDE WORSE THAN VW.

This is what I was getting to with regards to the whole N/A V8 thing. A dyno shows the result as much worse, but in terms of how 'alive' the car feels afterwards, it's night and day, better in every way, there's no copium, I prefer my 280kw setup over my 430kw setup. This was me doing predictions before I did the swap, I make about ~10kw more everywhere than the blue line, but chalk and cheese in terms of liveliness. I understand what Lithium is trying to say with his dyno graphs that look mostly the same in his case, but one is vastly superior in the real world. The blue line looks laughably bad on the dyno graph in my case, which really highlights the point. People absolutely, absolutely, completely underrate how important transient response is to how much fun a car is, how it feels, and how much you can trust a car, which means you can drive the thing faster, and if you are going faster and using 70% of the throttle, and trusting, and pushing, it's a far more fun, complete, and faster experience than feeling like you can't go beyond 50% of your throttle use but damn your dyno plot looks great.

Yeah, I mean the only photo I have seen is my own one, and looking at the ramp angles it FEELS like it's even front and back. The Nismo Pro being an adjustable uneven-ramp-1.5-way diff that-is-adjustable-ontop-of-that seems to account for everyone's experiences here.

I mean, the S15 has the same subframe as a R chassis, and had a Nismo diff in it. I'm confident that most people who think they have a "1.5" way diff just have a 1 way diff. I remain unconvinced unless they pull it apart and check. I have heard the PRO nismo is far less harsh but I mean not many people have driven them all back to back. It was absolutely not a nice little race car skip (like the GR Yaris I had which had 2x Mechanical diffs in it), it was more like someone hitting something with a hammer in the boot. (Or bad axle tramp). more BANG BANG BANG in slow, lound sounds than a skt-skt-skt of a locking diff. Interestingly, it was more skt-skt-skt on throttle. I have a helical now and I love it. If it dies, I'll find some kind of wavetrac or 370z quaife solution or god knows what. Or maybe drive a mechanical I HAVE DRIVEN before I buy another one blindly :p

Do you like axle tramp? Every time the clutch is out and you're off throttle at 30kmh or less? I tried lighter oils (Castrol's 90W?) and they were great, until they got sweated out in short order in street use. I tried heavier oils (260W Cusco? Some Jap brand now) and it stayed inside the diff, but driving around town off throttle was just vile. On throttle was noticeably less actually. It got to the point where the clutch was in every single time I was off throttle. Forever. Everywhere. People inside and outside of the car noticed it, people asked me at work why the car was broken and all sorts of stuff. I paid $1000 for the thing to be rebuilt and there was no issue found due to the fact the diff is designed to be that way. My car has always suffered from axle tramp mind you, trying to launch it at the edge of traction is pretty similar. Has all poly bushes (new) and pineapples have been tested in every configuration, nothing helped. The VLSD and Helical are smooth as silk. My mate's S15 with the 1 way drove like you would expect. Minor skipping on sharp angles on throttle, silent off throttle. Better in every single way, though I will say on track the 2 way is very predictable and does NOT want to kill you on decel like people fear, or seemed to fear back in the day.

Ye, depending on the percentages of the angles they could be a 1.9 way, or a 1.1 way, or a whatever way. Or maybe more accurately you could call it a "2" way (and Nismo does!) because there is some degree of locking in both directions. But I've never seen anyone talk about a plate diff in a skyline and use the term "ramp angle" and they absolutely haven't gone to Kazz and asked them what their ramp angles are, then compare them to Nismo, or Cusco etc. I think your post might be the first time I've ever seen someone consider a ramp angle or point out that it's customizable via Cusco! My 2 way with its nearly 45 degree ramp angles (just going by the picture) was an absolute piece of shit. (below 10kmh, daily driving). The one you want, whatever the part number is is clearly the 90 degree 1 way one.

There is no 1.5 way diff for Nismo, nor is there a 1.5 way diff at all, because all diffs that provide lock in both directions are by definition 2 way diffs. Having driven my _real_ 1.5 way diff and a real Nismo 1 way diff, the difference is very noticable and will send you insane thinking you are troubleshooting the same part. Observe the above diagram, then observe below: This is sold as a "Nismo 1.5 way" but is clearly a 1 way that my mate had. This is my "Nismo 1.5 way" that is actually a 1.5 way (maybe - The ramps look pretty even) but it is what people refer to as a "2 way" Nismo absolutely did (or used to) have different listings referring to different lockup types. From memory I saw it listed as "1 way" and "2 way" with no mention of the 1.5 way. Go by Nismo's recommendations and what you want in a road car is the Nismo "1" way. Potentially the adjustable pro 2 way can be made to be very relaxed on deceleration, or you are going to have a very skippy time relative to your friends with the 1 way version of the "1.5 way" This brought to you by a lot of pain and troubleshooting before opening the diff up. Get the right part numbers in your head from Nismo's page and get data like ramp angles and understand what they all are BEFORE BUYING A DIFF. What people refer to as a 1.5 way is merely a 2 way, but with locking ramps that are less severe on deceleration. 45 degree ramps are the most severe, so a 45 on accel and 45 on decel will be a true 2 way. Something like a 45 degree on acceleration and say a 65 degree on deceleration will be a "1.5" way. Something like 45 on accel and 90 degree on decel will be a 1 way. 90 degree ramps (which arent really a ramp) do not provide lockup. Look back at the differences between the two diff centers and you will be enlightened if not already

You could skip all of this silliness and put a V8 in from the start. You know where this ends

This is incredibly cheap. Mine is almost double.

Surely nowadays a G series can be done in a very-nearly-bolt-on-in-stock-location on a RB25 on a stock manifold etc. Surely. I have not really looked into it for reasons

Unkind reminder that VW SUV significantly less expensive and way more reliable than BMW sporty car. let alone a modified BMW sporty car.

Just to muddle things up. This is my GTX3076R compressor wheel which sounded great and was making 30psi and showed no performance problems. So who knows what's gonna happen

My problems are solved! Though to be honest (and be somewhat discouraging) I don't think it's a great plan. Mainly because even in V8 land if you stomp the throttle it's not some night and day difference say, under 4k. I tell people this all the time, my car makes ~210kw at 4k. If you floor it at 4k you get all the power and wildness that 210kw gets you. Not much really. If you floor it at 3k you get all the fury of ~130kw. And of course over 4k, well it makes less power than 90% of RB turbo setups. You could make the argument that "Well under 4k is where you spend most of your time driving" and that's true, except it's not like people are also spending their time driving under 4k at 100% throttle. Which means your intended speed really is determined by how fast the driver wants to go/whether you have traction. I don't think the PD is really a solid plan on a RB. People can commute around under 4k with a RB25 on 0psi just fine, and when your foot gets heavy people just don't stay under 4k and you get the best of both worlds. IMO the only benefit is mechanical simplicity/less internal issues, and partial throttle car-balance over 4000rpm. I sound like the ultimate wanker, but I will say that the LS really is a handling mod over anything else, in any area where the V8 N/A is comparable in power to a Turbo 2.5L or a PD driven 2.5L which for argument's sake we'll say is similar. (unless you want a scenario where you want 800KW where a RB+T is going to be just worse everywhere than a V8TT but that's not the discussion here :p)

I have what you want. A centrifugal charger could work (with regards to throttle respoonse), but it won't provide enough _power_ at lower RPM to feel like it's really giving you boost early. They really do feel identical to a larger, NA engine. The truth is I don't think this is going to exist anyway. I split multiple blocks purely on having too much power too early. POWER and low rpm equals a hell of a lot of torque, which creates all of the problems. I had a 2.8 with an EFR. It is as good as it's going to get. I guess you could go a 2.5 with a 7163 (or @CowsWithGuns's ill fated 7064), or go something silly like a bolt on manifold G25-550 with a .49 rear on a RB. I just don't think it's going to work. I guess someone could run a RB25 with a positive displacement blower, but I'm already scoffing at the first part of this sentence as I type it. I just can't see it working in any reasonable/practical fashion that results in happiness. My car drives really great and you should buy it. So I can buy.... something probably worse, as is the natural state of things. But I was the same line of thinking which lead to the heretic V8 decision. I wanted ~300kw of power, and I wanted that throttle response to be instant instead of waiting for 'laggy' EFR turbos to spin up, and that was with an EFR and a 2.8 running 11psi on the 7670.

Ahhh nah, my car is very high (relatively speaking), just has a non HICAS Subframe from a R34 (or S15, you know, it's all shared). I was under the impression I needed axles, the diff itself and subframe bushes and everything is entirely the same. Will obviously do more urgent research once "Ah f**k I've f**ked my diff, shit" happens, which may be never... I'm sure it's more complicated due to the fact I have a custom tailshaft already, but if you don't NEED a new tailshaft going to a 350z diff (i.e the OEM one bolts up and the dimensions are the same) then, woohoo, I guess.

I was under the impression that the 350Z diff was 'easy' (ish) I had planned to get a Quaife center in one if/when my current R34 helical gives up the ghost. How much pain am I actually in for trying to do this?

I mean with all the above taken into account, there's definitely some wisdom in just driving the fking thing, and a 250KW RB will not be in any danger with its low timing, low boost, and not making peak power at 7500rpm as you slam into the limiter. Conservative just means you're burning the candle more slowly after all, that has its own happy merits too.

6000rpm is weird. Usually the cutover point is half that. 3500. Could it be soft timing? I do not know. The way forward is gonna be check how those cams are degreed. Then get a second opinion/second tuner. The second opinion/second tuner could also be somebody who has installed RB cams before. They are stock cams, right? Of course, time poor and money poor does skew things.

I'm with Lithium on this one. What I'd actually love to see: a) More timing. Like 5 degrees+++ everywhere more timing. The old adage was "20 degrees at 20psi". You're nowhere near it. This is NOT a licence to just throw 5 degrees in and send it lol. b) An overlay of two runs, one with VCT off the entire run, and one with VCT on the entire run. This is usually how people decide the switching point. I know you said it was done at the tuner, but seeing those graphs would be very interesting. If one of the results from b) looks really strange, or the VCT switch over point is strange (like 6000+ rpm? or at 1000 rpm?) then that would be where you start looking as to how your cams have been physically set up.

That looks great, and I'm envious of your front bar fitment after having 'fun' with mine right now. I still don't understand the maths, because the new rear should poke 20mm further out than the new fronts do, but unless the rear got flared out 20mm more than the fronts did.. or you made a typo. Does look great though!

I mean, I hate to be that guy (cause I'll be poking the bear of further commentary) But you won't need additional mysterious arms for the car to not VEER left. I have stock arms. The car does not veer anywhere and toe is absolutely adjustable, as is camber (with an adjustable bush). If you have some scenario where the car is low as f*** then you may need aftermarket arms to dial camber OUT, but camber in and of itself does not make the car veer anywhere. Toe does. And toe is adjustable from the factory. Having 0 toe will result in the car going SLIGHTLY to the left on most roads due to the angle. It won't 'veer' and it won't make your tyres wear any faster, as they are following the curvature of the road. Dialling in alignment to counter that would be exactly as much wear as turning slightly to counter the curvature of the road because you're literally just baking that into the suspension. (more or less, someone pls correct me). At this point you need to post a vid, because every time you make a post Mr Silviaz, you get one step closer to explaining what is going on and 0.9 steps in another tangientally confusing area that requires much more clarification.