The Dan

there is a bad earth somewhere. good luck finding it. Make sure the earth to the block and battery is clean and free of corrosion. Also make sure they are connected tight. If you can't find any earth problem there, then look at the earths under the dash. You may find that the poor earth is draining your power also, as it will pull power away from you injectors when the ignition needs juice.

No, if the speedo is stuck at 0 then it may mean you are not moving, therfore you will get no boost. That is the only relationship they will have. HAve you checked all the vacuum line connections to the back of the plenum and the ones under the plenum? Have you checked all the fuses? Have you got a stuck open wastegate actuator or a soft actuator? What tune is in it? factory ECU? have you checked or changed spark plugs? Checked or adjusted ignition timing? The list goes on. Until someone can actually stand next to the thing and run some tests we can all stand around here making guesses. What is the extent of you mechanical knowledge? If none, then take it to someone. If you want to learn, then be prepared for it to take a long long time to fix your car.

there are also fuses in the engine bay. Check them also

Ok, I would start by topping up the power steering fluid. That should stop the HICAS light from coming on when you brake. If not, then there is a more serious problem...unable to diagnose here easily. Check all the fuses. The speedo works from a cable, all the rest work on electrical senders etc. Fuses are under the steering column to the side. Assuming you are in Aus yes? If you can hear the turbos spooling then it is likely you are making boost. Put a manual gauge on it to determine what level. If you are not, then look for leaks, if you are then do a compression test and suss out the condition of the rings etc. Come back with results and we'll try some more stuff.

That's reversion, not shuffling. The air chops back through the compressor and 'bounces' back and forth.

Might help if you state what car you are referring to. I assume you are not talking about the 300zx having the problem because of the comment "do these cars have the same ECU diagnostics as the 300zx?" Make and model, then people might be able to offer suggestions. I would recommend taking it to your preferred mechanic to have it resolved. With issues like that, I would say it will be difficult to E-fix

Does the compressor turn seperately to the turbine now? Back cutting the turbos compressor allows some air to pass on to the secondary blades which actually cools the charge air and allows you to run more boost and timing without the shuffle. If anything, it has improved response on the 4 cars I have done it on.

Read the bottom line in the paragraph you quoted.

Considering you were the one who brought it up, I think it is very relevant. You are talking about spending hundreds on a water pump to fix a supposed problem that really isn't there. I understand that these modified pumps do a much better job than the factory items when there is a need for this type of thing, but you asked for opinions, and my opinion is the same as 2LV8ETR - If it aint broke, don't fix it. Sure there is a place for this type of equipment, but so is there a place for using dry sump and external oil pump setups. DRIFTER seemed to have problems setting it up, which tells me that it's not something that just anyone can do as a simple, effective upgrade. It is impressive gear regardless, but you wanted peoples opinion and mentioned a 'common problem' as a good reason for upgrading. Without this 'common problem' there is no real reason for the average person to need it, so you will primarily be targeting a racer market. Both of the track cars I sponsor use an aftermarket alloy radiator (one uses PWR, the other - cooling pro from Justjap), a normal genuine water pump and normal off the shelf thermostat. 4 - 5 rounds on the race track with 20-30 minute breaks in between each round, in summer, and both of them maintain temps below 88deg. Once again, though, impressive product. It's good to see people thinking outside the box to make things better for all of us.

I fail to see why people think the Z is one of these laggy turbos. It is far from it. 1 bar at 3800rpm is not a laggy engine. I don't know if any of you have actually noticed when your power comes on with twins but -5's make a bar at 3800rpm also give or take a couple hundred depending on setup. -10's are another size up from this, so you can't expect them to perform as well as the Z, even on a single scroll manifold. Not all Z's are twin scroll either. 2.5-3L engines cannot make 600whp before 3500rpm so unless you go for N1's, you are not going to get the super response setup that everyone keeps talking about. Even factory GTR turbos are all in at 3200rpm. It just feels earlier because they don't make anywhere near the power. And what's stopping the guy with the big single from changing gear ratios in the box and diff? A motto I will stand by and prove fact every time is that anything over 350rwkw in a GTR and there is a single that will make the same power and come on boost slightly earlier than the twins before it.

I've pulled apart many many many RB's, 99.9% being daily drivers between 7-20 years old and have never ever seen a cracked cast valve guide. Not saying it doesn't happen but if it were common, then I'm sure I would have come across it by now. Also, the engineer I use (Chilton Engineering) does all the engineering work for Marty white, Chapman, GT Auto, BTT, and many others who all deal in RB's and he has never seen a cracked guide either...Not one single guide in 20 years. Worn guides yes, cracked..no. Once again, not saying it can't happen or doesn't happen, just saying it's not a 'common fault'

I would like to add, respectfully, that the cooling system is not exactly a weak spot for an RB. While improvements can be made, there are very basic steps that are fairly cheap to accomplish this. Furthermore, cracking valve guides is not a common occurrence so I would have to ask why you are worried about them cracking. I have seen bronze guides fail on 5 laps of QR in 4 or more different cars but never ever seen the cast guides crack. If they have been setup incorrectly or something else in the valvetrain comes adrift, then maybe. Under drive pulley will achieve the same result as an N1 water pump. and Redline Water wetter will decrease the surface tension of the water by decreasing cavitation.

That GTR that I listed has 0.9 rear. You can get them in: 0.84 0.96 1.00 1.14 1.15 1.32 1.52 1.75 I know that the Turbonetics housings bolt on to them so the ratios can be swapped around even more but pretty sure Garrett don't do a 0.7 rear and it's too late for me to ring and ask them. You would def want the 0.96, 1.00 or the 1.14 for the engine you have. If you don't care about the total figure (as you stated you only wanted 400kw) then I would go with the 1.00 to keep response as it'll still pull to 8500 quite nicely.

T04Z will out respond a pair of -10's IMO. With the right head work and the right tune. Strik3r just came off the dyno about half hour ago and he rang me with a 618hp at the wheels on 26psi. 1 bar at 3800rpm was pre tune, not sure what it does now but I'll post up the dyno charts if I get my hands on them soon. RB26DETT PowerFC D Jetro T04Z - Surge ported 6 Boost manifold 4 inch exhaust Full Tomei head with 270' 10.25mm lift. Splitfires and HKS twin power. Standard plenum The -10's should see a bar after 4krpm. T04Z is a winner IMO

I'm definitely not coming to yours for dinner if you use that for cookin your chips! You'd probably use 2 PAC primer to baste the chicken

+1

Run GTX2 in your engine and leave it there for 15,000km before changing it. Do that for 12-18 months and you will see what I mean with oil quality.

= Nasty Head

Yeah sorry I forgot to mention that. But IMO bush does not equal inferior. They have their applications but need to be well maintained and are less hard wearing so gunk in the oil can be quite damaging.

I can't imagine too many people here would be talking from experience considering it's a Skyline forum. But anyone who reads 1.06 automatically reads laggy. It's not that large a number really. 2.0 L engine go for the 0.6x, 2.5L engine go for the 0.8x, 3.0L engine go for the 1.0x Rotary = start at 1.0x and work your way up from there An effective power band is the biggest factor to consider. Don't pick a 1000hp turbo if you want boost before 4krpm. It just doesn't happen on anything less than a 6 or 7L engine. IMO a 1.06 A/R turbo would be absolutely perfect for your 3L engine but you won't see a bar of boost until 3800 or maybe even as late as 4k. But he will have an effective power band as any small capacity engine that wants to make power, needs to make it higher in the rev range.

Your turbo is already ball bearing. Highflowing the standard turbo would be a start. Around $1750-$1850 to do this so it's probably going to be one of the dearer 'bolt on' options. Garrett are currently working on a bolt on option for the Skyline but I still have to make the intake hard pipes and adaptors for them before they can be sent off for casting. The options for this come as GT2871, GT2876, GT3071 and GT3076. The 2871 being the closest option to standard but able to run up to around 1.6bar of boost safely. Other options are the Hypergear turbos, KKR turbos, or the Precision Highflows which use a GT cartridge also. These are all very close to bolt on options but require some adaptation to the intake system to get them to fit. I have had customers with the Precision and KKR turbos with great results and over 12 months of driving now without issues. I have never used the Hypergear version. The Hypergear and KKR options are probably your cheapest ones and you should be able to get them on including everything for ~$1000 The Garrett kits are still a couple of months away and will retail for up near $2400 I think. They will come with all the braided lines and piping kit to suit everything. For a complete bolt on application, though, you can't go past a factory high flow for quality and reliability. You just pay a fair bit more for the experience.

I wouldn't downsize the housing without upsizing the turbo. If you want to make 300awkw then you will do it with a GT3082 with a 1.06 rear. If you down size to the 0.82 it makes it harder without ballistic head work. So upsizing the turbo to the GT3582R with a 0.82 is a better option. With minimal head work, your 3L scooby doo would see 1 bar at around 3500-3800rpm with the 1.06 rear, 3000-3300 with a 0.82, 3200-3600 with a 35R / 0.82 rear but you'll make more power at less boost than the 0.82 on the 30R. Those engines are not overly efficient so you need to make best use of aftermarket head options. Start with cams, but if your budget allows, get the head porting and larger valves done too as it will knock you under the 3k mark with a 0.82 rear on a 30R if that's what you really want.

+1 I've never had issues with fitment on JJ kits. In fact they are one of the best intercoolers I have used to date for value/quality (not counting PWR) . We are using them in a couple of 5-600hp cars without issues and fitment was a breeze.

11-15 thou is what I normally see on aftermarket setups. Standard head, stick with standard clearance

And the relief valve is not the only thing effecting pressure. It could be stuck open or stuck closed. ...or it could be fine. Get it checked with a manual gauge. I'm sure it is fine. Worry about it later once you have the results of that test