GTSBoy

I mean runner lengths as anything that you can optimise in terms of matching the lengths or trying to make them the "right" length. I otherwise concur (and have already said so) that shorter is better. I think the energy lost from long pipes is part of it, but I think the bloody torturous path from under the motor to the turbine inlet has got to be at least as significant. The funky exhaust pulse pattern can't help either. On the subject of the T1 dampener - I'm not knocking them at all. I use snubbers like that on industrial sensing applications** to knock the spikes out of pressure signals. Actually, I'm only assuming that they are like what I use, which are mostly just sintered metal inside. The T1 snubbers could be a little more sophisticated, ref their claims of temperature reduction, etc. Given where they install them (on the RB38 head) - they're not actually in a "bad" physical situation. As to the delay - any device which is capable of providing the required smoothing will cause a similar delay. Doesn't matter if physical or electronic. **Like low pressure switches on gas valve trains, where opening the safety shutoff valves to the burner can cause the gas pressure to drop below the switch point briefly. The snubber can prevent unwanted trips.

Yeah, I was more spraying into the thread in general. But wrt spool.....the revs are even lower, so the whole concept of runner lengths becomes even more meaningless. And while I agree that how the whole lot works before you get boost is very important, for all the reasons that we all know, in reality there is no hope of pulse tuning to make the manifold work well in an NA sense, and the turbine is always a restriction in the exhaust, even before you get any boost, and the pressure has to be positive and rising all through the spool period, taking us further and further away from the regime where any sort of pulse tuning at the port helps. I wasn't suggesting that the EMAP was steady - just that there is a large floor level of positive pressure with the pulses on top. Those snubbers in your link highlight the issue. Whatever "steady" pressure you get from those is the average pressure, but the lowest pressure will not be that far below that average. I haven't logged anything myself, so I'm working from mental modelling. So here's a question for anyone who's logged EMAP without any snubbers or heavy electronic filtering.....What is the top and bottom of the pressure fluctuation range compared to the average value? +/- 5%? 10%? 25%? ie, how noisy does the signal look? FWIW also, the blurb for those snubbers says that electronic filtering causes a delay in the measurement. Well, yes. But so does pneumatic filtering. Filtering is still filtering and putting a pulsation damper into a pneumatic signal line works by blurring the fluctuations together, which inherently means a delay, probably exactly equivalent to the electronic one.

Obviously the subject is huge, but there are a couple of points to remember when pondering runner lengths, pulse tuning and pulse interference. 1. On an NA tuned length manifold, the lengths of the runners are "tuned" to get the pulses to come through the collector in a tidy order over a relatively narrow range of revs. They have to be long (like many inches for each of the primary and secondary pipes) in order to actually get the tuning in the desired rpm band. 2. The tuning means that you get a little extra low pressure at the exhaust port that has an opening valve. 3. When you are not in that rev range, you don't get that. You will actually end up with a little extra positive pressure on the port at certain rpm ranges. Yet the engine still works. 4. Turbo manifolds are obviously a lot shorter. So....their rpm "tuning" would be for much much higher revs, if they were tuned at all. But they're not really "tuned", because the engines don't run at those revs. 5. So the primary concern over any "equal length" runner business should be to try to get the pulses to arrive at the turbo in a polite order across as wide a range of revs as possible. That way they don't pile up on each other if a pair of pulses arrive at overlapping time. I suspect the only way to get 5 to work is with equal length pipes, or maybe, just maybe, pipes with integer divisor lengths. But I wouldn't bank on it (the integer divisor length bit). There's a few more points to make about that. 6. The raw gas velocity in the runners can be more or less calculated simply from the total (actual, hot, pressurised) flow rate and the cross-sectional area of the runner. Of course, because it is pulsatory, the peak velocity is going to be higher, blah blah blah. But you can work out the order of magnitude of the velocity. And when you do, you find that the travel time from port to turbo is really really really small. So if you have different runner lengths at all, you are going to struggle to get a non-interfering collection of the pulses. 7. Keep in mind that the static pressure of the manifold (once up on boost) is pretty steady. The exhaust pulses might be happening, but the whole manifold is up at 15 or 20 or 30 psi. Clearly, the exit flow from the manifold out through the turbine and the exhaust is nowhere near as pulsatory as all the above discussion makes out. There is a large base flow rate and the pulses just vary the top X% of the flow. I'll be f**ked if I'm going to try to do any of the maths for all of that though! Don't need the head pain. 8. I think the conclusion has been reached and discussed so many times in the past that it probably doesn't need reiteration. But just in case.....the tidiness of the pipework is more important than the lengths in a turbo manifold. The whole concept of length tuning is not relevant at the short lengths being considered. Even trying to arrange for equal length pipes is fraught with the question..."exactly what is the length of this pipe anyway?". By that I mean, where are you measuring from? The valve, the port lip? Where are you measuring to? The start of the "collector"? The turbo flange? The end of the nozzle in the turbine housing? What line are you measuring along? The centreline of the pipe? What about where you have two pipes merging on an angle? etc etc etc bastard math blah blah blah. Make 'em short and sweet is as good a guideline as any other. If you could make them equal length, you will at least avoid the issue of the pulses piling up. But the cast 3 cylinder manifolds seldom have the middle runner as long as the outers....so that's out the window. And, one last thought.....On an NA manifold the little bit of suction that you get at the port from tuned pulses doing their things at the collector is a reasonably large effect - because the manifold pressure is not very high. The suction represents a larger fraction of the base pressure, has a noticeable effect. In a turbo manifold, with the running pressure being so high, the pressure pulses turning up at the ports, whether positive or negative (relative to the base pressure) are much smaller, relative to the base pressure, so their contributions to adding or subtracting flow through the port are reduced. Still there, but not really in the realms of "free power" like they are on NAs.

Yes you are. The Hagen-Poiseville equation ignores entry and exit effects, etc, as I said before. Pressure and pipe resistance are basically equivalent to voltage and electrical resistance. You get a reasonably simple relationship where the flow is directly proportional to the driving force and inversely proportional to the resistance. The H-P equation just wraps up the diameter to area relationship along with the other factors in one equation. It actually hides a lot of thinking. R^4 for example, is actually R^2, just mentioned twice. One of them is the pipe area considering its effect on the flow capacity (the bigger it is the more it will flow). The 8 comes from a number of divide by 2s. The L is only the bottom line of the equation because the longer the pipe, the higher the resistance to flow. But as I said, the pipe does not exist in isolation.

Read my reply above, then stop. You are trying to work with just one element in the middle of a system. If you don't consider the whole system, you come to the wrong conclusions. Pressure drop (loss of energy) in pipe flow stems from internal friction (viscous effects in the fluid flow) and from wall friction. Add fittings (bend, tees, orifices, changes in section, etc) and you get more of each of those. All governed by some ridiculous equations (Bernoullis, etc) that are effectively insoluble for real people with calculators. We don't even solve the real equations when we're doing CFD unless it's a simple problem and you have an enormous computer available. In CFD we use dramatically simplified models to do the turbulence calculations

Yup, search for the other 6*10^16 threads asking the same question.

Same same - unless the GTR ones have an extra flap/hatch to access the ATESSA stuff on the RHS. I can't remember.

Oh heck! I didn't even read that. It's absolutely not true. Not even close. The length of the manifold runner contributes a TINY percentage of the total resistance to flow in the inlet-engine-exhaust-turbo-exhaust flow path. Even if you ignore everything upstream of the exhaust valve, the fraction of the resistance coming from the runner length is almost nil. The only time that the quoted statement is remotely close to being true is when there is the pipe and nothing but the pipe. Like a pipe on the outlet of a fan. And even then it's not true, because there are fixed entry and exit pressure drops associated with any pipe. Time for a thought experiment. Blow through a 6" long drinking straw. Measure the flow. Now do it with a 12" long straw. You won't have half the flow rate.

Head lamp fuses are all present. They're at the top (of the image) of the vertical row of fuses in the centre of the box. The vacant headlamp "big box" is a relay location. Not sure if you need it on that car. There is one at the other end of the fusebox.

Or bad coil wiring that you have disturbed by pulling it apart.

Heat loss can probably be more than sufficiently mitigated with ceramic coating though. I think beyond that, the question is not really amenable to thought experiment. The variables are non-linear and it's not really possible to say which one has the bigger effect at the exact conditions in play. Would make a lovely episode of Engine Masters though.

I haven't done the thing myself (being in a 32 it would be a lot more trouble than I am willing to go through). But I am with those guys^.

Maybe, but there are other options. There are some Australian coilover options which are top notch. Jap stuff tends to be pretty harsh. I know nothing of JRZ in terms of their goodness/reputation, but so long as their dampers are good, then it doesn't matter if that noise is a dud damper or a noisy top ball. There are fixes for both. FWIW, I wouldn't consider a pillowball top on any strut top on a road car. Just not a good choice. There are a few places where it is good to have something with some compliance in it, and that is one of them. Perhaps ask JRZ if they have a rubber top for these things. It's not like you need the extra 0.25mm of stiffness in the rear dampers anyway!

If you're not budgeting on taking the boot to a panel beater to have the holes welded and the whole thing repainted, you're thinking about it correctly anyway.

Either just tape the sensor up out of the way or weld a bung in for it. Neither are difficult nor destructive. As to why Nismo didn't make a spot for it......the original system has one cat, hence one good spot to fit a single sensor. The Nismo system has 2 cats, so it doesn't have a good spot to fit a single sensor. Seeing as fitting such a system implies no longer giving a f**k about trivial things like cat over temp sensors, they took the sensible approach and omitted it. Besides, if you had it, and you had a fault on the other pipe....you wouldn't know. Better to have your ignorance spread evenly over both pipes.

The R32 GTR manual has everything you need. Yes, including the TCU wiring for non-GTR autos. Because it also covers GTS4s, including autos. The AWD and RWD turbo and NA autos are all similar enough wrt the power button and TCU interface. You should consider getting it to a mechanic who has a good diagnostic scanner and find out what codes the TCU might be suffering with.

What do you mean by "return flow"? Do you mean, "Return flow", as in the intercooler itself is set up to take both pipes approaching from the passenger side, or do you mean the FMIC is conventional straight through and then you have to get the cold side pipe up from the driver's side, across the car and back to the stock TB? Because the first way looks fine, but is a bit limited in how much power it can handle, and the second way always looks like balls.

It's time to say the "R". That would be the Golf R.

I don't even bother with torque wrenches. Suspension bolts are done up somewhere between f**king tight and real f**king tight. As hard as you can manage with a breaker bar and a double ended ring spanner is pretty good.

I've typed many thousands of words on this subject into these forums. You should do some searching, 'coz I'm not inclined to type them all again right now. The answers are here though.

Check for a slipped crank pulley. The timing marks could be telling you lies.#1 plug out and screwdriver down the hole looking for TDC would be the first step there. Remember that an RB20 has a switch in the TPS for idle. It doesn't rely on the ~0.45v that the 25s do. Otherwise, your weird issue is weird and will always be something unexpected!

If that's the strut itself, it's no damn good - it's buggered. If it's the spherical joint at the top, then it's unpleasantly noisy and probably shouldn't be that bad. Either way, JRZ will/should come to the party I think.

Solid lifters may never need clearance adjustment. Most good Jap motors never show any wear on the valve train if looked after, and don't suffer valve seat recession either. But....these things can happen. You only need some oil starvation from a blocked gallery to cause a spot to wear. So, no common problems on these, but all the possible problems are possible. Rip the covers off and use feeler gauges to determine the cold clearances and work from there.

But that would be a genuine Nissan one, which would be the best choice and wouldn't need to be opened up for surgery anyway, for the next 20 years at least. Having said that.....if the OP's clutch can be opened, then yes....great. Consider the surgical option.