Dale FZ1

Other than because you can do it, why would you want your car to sound like it's poorly tuned? I recall some comments from him about ignition timing, but suspect it was in relation to tuning for emissions. Less advance generally equates to higher exhaust temps. My understanding is that extra advance will result in more efficient running + torque, but past a certain point the emissions output is increased in a certain area. So there is a sweet point for tuning for either emissions or torque, but they are often different. Browsing Guilt Toy's thread about emissions sort of covered his findings.

The CAS uses the signal to determine the position of the CRANK, not the camshaft. It's just convenient to mount the sensor on the end of the cam. So reset your timing to 15 degrees. Remember the timing event is described in relation to TDC - Top Dead Centre of the piston through its stroke. So it's all about the crank position.

If you pull off the CAS to adjust the cam gear, then good practice is to use your timing light and adjust your ignition to the same base timing. Otherwise yes, the whole timing map will be out by that amount. Here's something about the two maps: IGN. for full load tuning use Map Watch to follow the diagonal downwards ramp as the engine accelerates from say 1600rpm to 4800. Aim to make the progressive reduction in timing incremental (ie no huge steps). Watch your knock counts in those cells, and be aware of interpolation from adjoining cells. Interpolation is something to be aware of particularly for full load fuel settings as well. This can make it difficult to get a particular cell "nice" because of an artificial raise or drop in fuel or ignition for that cell because of the variance in its neighbour. INJ. especially on very light trailing throttle decel as you go from load row 2 to row 1 where decel fuel cut occurs, it can be difficult to eliminate a slight throttle hunt that feels like it cycles on-off-on-off-on-off. If you get that feel, check the AFR log via a chart to verify. I have run row 2 very lean (around 15.5 AFR) and it was terrible. At around 13.5 the hunt is greatly reduced but still slightly noticeable. Trying to get any meaningful log of AFR on row 1 is virtually pointless due to decel fuel cut. As per Mafia's comments, some of the other settings that can be adjusted are worth reviewing too.

All of the available kits that I know of use some load-sensing method to trigger induction of water. That could be boost, or voltage from MAF or TPS. I don’t think that WI response to knock sensor output would be quick enough to control onset of detonation. So basically above the tuner’s preferred threshold the coolant (water, or water/meth) is used to prevent rather than eliminate knock that has already started. There is a train of thought that nozzle placement further away from the inlet valve allows more time for conversion of the coolant from liquid to gaseous state, so there may be some air density increase depending on the installed location. Using a single nozzle could create the possibility of uneven distribution to cylinders, depending on manifold design and whether the conversion of state of the coolant facilitates less resistance to change of direction and distribution. Multi nozzle setups require some thought into even pressure distribution, so have their own design issues. I agree the concept of higher static C.R. has its attractions, but it’s difficult to cite the Gibson Racing Group A cars as directly comparable examples. Reliable information from a mate who worked around the circus in those days indicates that the fuels were definitely exotic potions. No prizes for guessing why a certain red #17 car sponsored by Shell was acknowledged as about the most powerful of its breed. I’ve looked at the 10:1 DE+T concept combined with water injection, but specific advice from a Cairns based expert was that the benefit:cost did not stack up well. There is much more off-boost torque to be had via cubic inches than via higher compression, for example. The one thing that does seem to shine through is that there is a power level below which WI is of questionable value, and above which it’s extremely beneficial. Good discussion BTW, and hopefully Mafia and others can chime in with some more experiences.

Not sure I understand this comment? Trigger the water flow according to the 0-5V MAF output, and pick up the pump duty cycle to suit. The highest % water:fuel is actually required around peak torque rpm because this is where peak work is actually done and detonation is most prevalent. The performance diesel scene in the US is well versed in WI. Tractor pulls, and those lunatics who drag race their Dodge Ram utes and the like find great use for it. They do run boost pressures up around 90psi and have specific power outputs along the lines of a good petrol engine, so they are fueling them right up and would have combustion temps that would otherwise melt things. Obviously the water does a different job in a compression ignition engine. As an aside, there is a Queensland company prototyping a secondary LPG injection system for use in light/medium trucks that seems to have great merit. The liquid gas acts to cool things and promote greater burn efficiency. They claim greater power/driveability and older engines are meeting current and future emissions targets. Packaging size would probably preclude its use in a Hyundai i30 or VW Polo though. Staged secondary nozzle activation could be done, but complexity is going upwards. If you were doing that, it would probably be wise to invest in a system that uses high speed solenoid water delivery. Basically works the same as a fuel injector but capable of handling water without corroding shut. Higher compression has its merits, but the overall engine configuration has to be geared towards the overall power output. ie. you'd need to do a bit of homework on effective dynamic compression ratios which factors in cam profile + timing, and turbo spec. If you went too far out on a limb chasing efficiency then something relating to engine reliability is going to suffer. Depending on the approach to tuning with/for WI, it becomes an additional system that requires absolute reliability (NO failures) the same as fuel, cooling, and lubrication. Fortunately there are some clever blokes out there, and some kits offer low water/nozzle blocked warnings and fail safe fuel/ignition mapping interventions. The point is that you would need to be careful as to how the WI is integrated into the tuning, and choice of engine spec.

The key to getting optimal results is in matching water:fuel:air ratios, and hence knowing the delivery ramp rate of fuel, and of the water system as well. Maths will get a smart punter in the ballpark. Adrian's suggestion of using WI at low loads is not inherently bad, though we don' seem to have any evidence in the field that anyone does it. All the evidence points towards its benefits being an anti-detonant at high loads. For light load, it could be that virtually constant use would require a large storage tank - leading to packaging (size constraint) and excessive weight gain vs tangible benefit issues. The other thing that might make a lot of work would be sizing nozzles capable of proper atomisation to match low fuel flow rates, and then having enough capacity to match the injectors when running at full noise. Sounds difficult unless using a high speed solenoid valve, which is expensive and might be difficult to interface with the ECU. To me it is significant that the NACA aero research focused on WI as a way of running their engines at a higher maximum power output, while using lower grade fuel, and less of it. Replacing fuel with a certain amount of water improved military outcomes at a lower cost. The capacity of those aero engines, and power output meant that they were airborne fuel tankers with bombs and bullets. Literally able to consume hundreds of gallons of aviation fuel per hour. Military honchos had to work out how to stay in the fight but cut their fuel bills. Particularly for a performance car application, I would stick with proven outcomes and target more reliable, knock free power at maybe slightly reduced fuel consumption. Grigor's information is correct, and gearing your controller to take multiple inputs is relatively simple. Same as tuning your fuel and ignition, though the practice of getting it "right" may take some effort. All the same, Mafia's results are testimony to good outcomes using progressive delivery based solely on boost.

I don't want to labour on duty cycles either, so can you post up the sheet on the result here? 270kW @ ~17psi with a 3076 on an RB25 is fairly typical, and a good stout result. I saw from one of your posts that you are running an external gate. What manifold is it all bolted to?

Moving to a GT30 based turbo will be something that should make you smile each time you drive it. The highflows weren't from Slide were they? There was a few reported failures that seemed related to quality control in assembly/manufacture, rather than anything done/not done on the owner's part after they were fitted. Main point being, if you are going GT30, do it now rather than spending the time refitting a stocker.

Check this thread: http://www.skylinesaustralia.com/forums/Ga...io-t207931.html The on-road results for the 0.63 seem pretty good, but there may be some issues with boost control by the sounds of things. They certainly seem to give a big whack of early response, and depending on needs and preferences that may give more torque, earlier, than some people want. Definitely ask Mafia and BHDave what is their general view on this characteristic. The consensus amongst those of us with a turbine A/R of 0.82 (or 0.87 HKS version) is of progressive, driveable response. Haven't heard a complaint yet. At 270kW it might be a technical difference between 3071 and 3076 rather than something that you can feel or measure, if response is the goal. As always, it depends on the use of the vehicle, and skill/preference of the driver.

And it is. Sometimes people have to step sideways to move forwards. Up in a bigger league, the GTRS may look a little insipid, but I don't think it's at all disgraced. The strangest thing about upsizing is the different feeling of response. Maybe the sounds contribute to that as well?

Depending on spec, it is possible to make a massive mid range torque number but not a correspondingly large power number. The issue is whether the torque graph has a profile like this: or this: Power is just a function of torque and revs, so if the torque doesn't hold up, it won't show a lot of power. The 34mm intake restrictor mandated in the ARC rally cars keeps maximum power right down, so they have to make the things tractor down in the rev range and keep pulling gears. I'd suggest looking at the shape of the curve, and area under the curve rather than a peak number. cheers

Well this should give an indicator of what a 3037 can do with reasonably good tuning on an internally stock engine and running a free flowing (reasonably noisy) exhaust. That is ~ 290kW for the mathematically challenged, with boost peaking @ 18.6psi and tapering to 18.0psi using a Turbotech adjuster. AFR is held steady @ 11.95-12.1, and max reported knock was 16. Slightly shaky looking graph at the top end indicates it wants more ignition, but that results in higher knock figures. I have a solution to that issue. Running with an extra baffle, power drops 24hp to ~ 270kW, and the increased backpressure holds boost back to 17.3psi. There are no complaints about either delivery or quantity of power.

You could always post up the question to the seller to provide more detail. He has them listed as GT3060, so odds on he's got it wrong and they are GT2560 of some description. Normal type advice is to ask for the cartridge number and you will identify what they are without a problem. Clarify the ambiguity if you can, and there might be a decent buy for you. Who knows until you ask the questions of the seller? Good luck.

given it only appears to have a single turbine inlet, that would seem to belong on a VG30DETT. Also the comp cover looks different to the DET version that comes with an OP6 turbine housing.

I'd say it's hungry for a bit of timing.

Post it up for all to see. I'm interested in the results.

Without a doubt, and point taken. Where I saw the advantage of the 71 was right down low. The one weakness I perceive in the 3037/3076 after stepping up from a 2871 hybrid is from 2000-2500rpm. Previously it was very athletic in that range, but now it feels "torquey" while gathering momentum. By way of comparison with Dave's observed rate of spool, I will see around 4psi @ 2400 if I accelerate it in 5th from 2000rpm. Not weak or laggy, just not ballsy in that range. From 2700-7000 is just a massive torque wave. I have a strong interest in the outcomes here, mainly because until this HKS came along, my intention was to order the 3071 / 0.63 combination.

12.5 l/100km, mathmatical average over 35000km. This includes all tuning and motorsports activities. Worst result was around 19, best around 10. Driver behaviour has a lot to do with it.

skylinecouple actually seemed to have an opinion from the other angle, and last I heard from him he was about to replace the 3071 with a 3076. Looking at the maps, picking an arbitrary 2.5PR that would be necessary to pull the sort of hp these things are capable of, the 76 actually has a wider map than the 71. The difference is that the 71 actually hits on its peak efficiency through the midrange rpm (say at peak engine torque) while the 76 just misses it. Running a 0.7A/R TO4S type cover might yield a higher flow capacity, but have a bad impact on spool/response. There's a lot more internal capacity to pressurise. I'd say it's more likely that to pull every last pound of airflow from the 76 it would probably need the 1.06 turbine housing and there goes your bottom end spool. I can advise that the 3037/3076 running a 0.87 HKS turbine housing does not feel compromised on a stock RB25 for overall response, boost threshold, or maximum power output. I know it is a very good unit, but there are varying preferences out there. I think BHDave is on the money with needing to spin the 71 harder, earlier, in order to make it respond and get the theoretical response improvement over a 76. But the smaller 0.63 housing will choke a little earlier. I'd say that driver preference and maybe intended use of the car would be a deciding factor here. It would be prudent to look at "response" from a couple of angles. You have boost response, engine response, and the intangible "feel". It might be that the 71 particularly with a 0.63 housing is a bit too touchy for some, and gives more/quicker torque delivery than desired. Personally I want tyres that are turnin', not burnin' Playing around with jetting on bikes a couple of years back, one of my dyno operator's tricks was to review an acceleration run through the gears, vs time. That test could be done using any particular rpm for change point, and was not only a way of looking at power output but type and rate of delivery. Believe me that is an important factor on two wheels. That might just put some of skylinecouple's choices regarding the 0.82 housing and a 76 v 71 choice in perspective. Too much off topic, and apologies to BHDave. I am pretty interested to see what happens over the next week for him, and hopefully a bit of work around the wastegate area will get the boost controlled properly.

It would be best to hear the impressions direct from skylinecouple, but I do know he has a pretty busy schedule and checks the forum infrequently. He is running fairly conventional supporting system upgrades with the -23 60mm turbine 0.82 IW version of the 3071. Sourced from the US, and yes it is the same family of housings we are all talking about. Numbers wise I think he indicated it's making around 260kW @ 17psi and running reasonably rich with conservative timing. Evidently it runs quite linear delivery with maybe a touch higher boost threshold than his old GCG high flow, but the higher end breathing is freed up and it pulls very hard right through to above 7000 as boost builds quickly. Apparently wet roads and those steel joining strips on some roads can result in unexpected (unintended) traction loss that never happened with his high flow turbo setup. We spoke at length, and he felt that there may have been no practical benefit of the 3071 + 0.82 over a 3076 with the same turbine housing. But the whole time he enthused over the linearity and overall feel of the setup. If you read his thread regarding this turbo, that was one of his primary aims along with removing turbine back pressure.

I believe Cubes had experience with the availability of an upsized wastegate port + valve after Garrett had a few of these GT30 housings running in service. I think there was a -M suffix put on the part number to indicate it. The size change wasn't massive, and the job on an existing unit isn't big either. But 3-4mm would be a large increase in cross sectional area. An upgrade would probably require a larger valve. I would think that the valve would need around 3mm to be seating "nicely" and allow for the bit of float that occurs.

If boost is creeping as revs rise, it's starting to sound like wastegate size is inadequate. Dave was yours one of the production upgrade housings, with the bigger valve already fitted? Or do you know the size of the valve and port? It would be interesting to know how it compares to a HKS Pro S in that respect. I also think there might be a few too many differences between the GT30 and GT35 to bring direct comparison with dangerman4's setup. The casting may be the same, but there is a much bigger vent area through the turbine. But I do see your point. I know skylinecouple was/is running a 0.82 IW housing on his 3071, and don't believe there was any boost control issues there. But I'm not sure if he had the upsized wastegate.

Adrian what will you actually shell out for, now that you've been running the R33 for some time? And when? - I'd like to see/hear the results of your own upgrade.

The common factor I see between Dave and Andrew's setup is using an EBC, and inaccurate boost control. What is good, is that you are both seeing boost coming back to target at higher rpm, so the venting capacity of the wastegate + dump is not likely the culprit. It would be interesting to know what strength actuator you are both currently running. Currently I think dangerman4 probably has the best solution

If running only pneumatic control straight to actuator, the last few psi should be a little gradual, as the valve has already moved off its seat. If there is some sort of interference type controller (eg EBC, turbotech) then yes, it should ramp really hard virtually up to the targeted level. And depending on how good the setup is, I'd say to expect a slight spike before settling to what you wanted. It does make sense to use an actuator of the weight close to your boost target.