Warpspeed

To be honest, any car that is nearly twenty years old will have seen a lot of miles. A performance car will have seen some thrashing too. Nobody buys a GTR to only drive to church on Sundays. Now you might thing that a new set of rings, a valve job and a new clutch will restore the whole car to as new showroom condition. Sadly that is never true. Old cars have things like collapsed drivers seat, worn out window winders, worn gearbox synchros, and ten thousand other annoying little problems. Quite a few will have been pranged and repaired, maybe pranged several times. To fix everything is just not realistic. If all you want is a fast car, and could not care less about the fluid leaks, body filler, panels that don't meet properly, gearbox crunches, or the funny noises from the suspension, fine. Just realize it is an old tired car, You may get lucky and find one that has belonged to some crazy millionaire, hardly ever driven, and has only done 5,000 Km, but don't count on it. The truth is, you get what you pay for. And sometimes a lot less than you pay for.

You guys can all laugh, but there IS a definite relationship. Basically 6cc per minute per flywheel horsepower is a very close approximation of fuel flow at optimum air fuel ratio. As you have six cylinders, and six injectors, that means max flywheel horsepower = Injector flow at 100 percent duty cycle. So basically 550cc injectors would equal 550 flywheel horsepower absolutely flat out at full maximum duty cycle. But that is not real smart. You might want to limit it to 80% duty cycle maybe ? Which would be only 440 flywheel Hp. But then there are drive train losses, typically only 85% of flywheel power makes it to the rear, so that comes to 374 Hp. Converted to Kw that is 275 RWKw. Depending on the injectors you run, and assuming the fuel pump is up to the job you CAN figure out a reasonable RWKw versus injector size. So absolutely balls to the wall with no margin might be injector size in cc x 0.85 x 0.746 = RWKw Something safer and more reasonable might be injector size in cc x 0.8 x 0.85 x 0.746 = RWKw

Yeah it has a xenon push pull spool up valve you connect to your nitrous bottle. When you hit boost it opens the screamer pipe. Great for doing burnouts during the school holidays.

I have heard that too, but I ran one for three years without any problems with the movable vanes. Porsche now use these turbos on the current 911, so reliability cannot be too bad. Fitting a wastegate is no problem, but what sort of control strategy would you use to control both vane position and wastegate. Think about all this very carefully, and figure out a simple way that does not require full electronic control by the engine management system. There is no simple way, that is the problem. Yes obviously. You could fit an enormous turbine and housing, but then even with the movable vanes, a GT ball bearing turbo would leave it for dead response wise. Yes, they are good arent they ! But they are diesels not petrol engines, the air (andexhaust flow) is not throttled as it is with a petrol engine. Why don't BMW use it on their turbo petrol engines if it works so well ? Their current turbo petrol engines all use wastegates. It is nice to speculate. Why do you think Garrett have never fitted variable vane turbines on their GT ball bearing turbos ? If it really worked, companies like HKS would be selling premium performance VNT turbos in all sizes to the hot rodders. If it was all that good why have the drag racers and rally cars not bothered to use VNT technology ???? The answer is, it has been tried by almost everyone, and it is a real BUMMER. It creates far more problems than it solves on a petrol engine, but works wonderfully well on an unthrottled diesel. But getting back on topic. I have even tried using a split pulse turbine housing with a second wastegate to block one side of the turbine. Use half the a/r to spool up, then open the wastegate to double the effective a/r to reduce turbine back pressure while holding full boost. A second wastegate then works in the normal way. I have actually tried this too, and it works. But the improvement is barely noticeable, and it is just not worth doing.

O/k guys, split pulse housings can sometimes help, and sometimes make no difference. Where a split pulse housing can really help is where there are very few cylinders. You get an exhaust pop, then nothing happens for quite a while, then you get another exhaust pop. Take an extreme example of a twin cylinder motorcycle engine where both pistons go up and down together, and there is one power stroke every 360 crank degrees. Now a turbine with two inlets, each with an a/r of say 0.3 is going to work a lot better than a single entry turbine with an a/r of 0.6 The whole thing will still have the same total flow capacity of the larger housing, but a split pulse half housing will really help it at low rpm where every exhaust pop goes into a much smaller turbine scroll of only half the total flow area. High gas velocity is maintained and the turbine gets a really good good kick every exhaust pop. Now think of the other extreme, a V12 engine. Each bank will have six cylinders, and there are so many overlapping exhaust pulses that the exhaust flow is almost continuous by the time it reaches the turbo. A split housing will be zero advantage. So you could say that a four cylinder engine will probably gain from having a split pulse housing, and a V8 definitely will not. A six cylinder engine is right smack in the middle. A six cylinder engine fires three times per revolution, and each group of three cylinders fires three times every two revolutions, or every 240 crank degrees. If the exhaust cam has 240 degrees duration, then there is no exhaust ovelap between cylinders in each group of three. But neither is there any pause between exhaust pops in each three cylinder group. So a split pulse housing on a six cylinder offers no real advantage. If it did, you can be sure Nissan would have built it that way. A much better idea is to use a single entry housing with six individual runners correctly aimed into the turbine. This has been proved time after time as being the optimum design for an inline six. Don't bother dreaming about the variable vane turbines, they just don't work very well on petrol engines. These things have been around now for twenty years, Nissan COULD have used them on the original R32 GTR if the idea worked, the technology was available back then. The biggest problem is that ALL the exhaust has to go through the turbine all of the time. This creates massive exhaust back pressure. The vanes can certainly reduce turbine rpm, but the cannot increase the physical flow area inside the turbine housing. I am speaking from experience, I have fitted a Garrett VNT turbo to my engine, it was very responsive, strong mid range, and absolutely hopeless top end power. Stick with the Garrett GT series ball bearing turbos. If VNT turbos worked on petrol engines, Garrett would be advertising them as such. They only work properly on diesels. Porsche are the only manufacturer to use them, and they also run wastegates, and the whole thing is controlled by the engine management unit. I have messed around with VNT turbos myself for three years, and so have many others. Where are all the fast drag cars running VNT turbos ? Almost everyone has tried it and given up. If you want to do a whole lot better than a GT ball bearing turbo, consider twincharging. I have tried that too, and can thoroughly recommend it.

If I was doing this, I would do the 2.4 stroker conversion. That would give you the torque increase you want, and there is no way the insurance company are ever going to know. I would also fit a power FC, and then get the car properly dyno tuned. The whole thing should then run pretty well, and the engine still looks completely standard and original.

Apparently nobody here is learning anything at all. We have another guy just arrived here Turbo65Falcon, he is now going to try this too. And they just keep on coming. I am not here to put you guys down, just trying to save people a hell of a lot of work and effort for nothing, but nobody listens. Worse than that, people object when I try to help. So I am not going to bother anymore.

Yes and no. Engineering is all about calculating stress and fatigue limits, and staying within known and reasonable bounds. The guys that design and build bridges and high rise buildings do not build whole bridges or buildings and then test them to destruction !! There is a lot you can tell by just calculation, or these days computer simulation. Crankshaft resonances and harmonic damper (balance) design is not a hit or miss affair. Neither is the correct sizing or placement of counterweights just guessed at. No need to place an engine on a dyno and flog it to death for hundreds of hours, although the big car manufacturers still regularly do this as routine with their new designs. I doubt if any aircraft flown today is actually stressed to the point where the wings rip off, just to see what speed that actually is. Engineering has come a long way over the last few hundred years. Yet drag racers will build and run an engine on the strip until it breaks. Then try again. "If you ain't bustin stuff on the strip, you just ain't tryin hard enuff". But most of these guys are not real engineers, and would you trust these blokes to design a passenger aircraft in which your family would fly?

The thing that makes the 2Jz superior is the crankshaft design and the extra capacity, and only that. RB30 was available for Nissan to use in the GTR if they had wanted to. Why do you suppose they only used the RB30 bottom end on the low revving Australian "taxi" engine. Nissan could have built a twelve counterweight forged crank, and built a factory RB30DETT for the GTR easily enough, but they chose not to. The RB26DETT is a much better balanced overall design for a high revving endurance race engine. Its competition success and reliability speaks for itself. While hot rodders can certainly extract big power from an RB30DETT combination, it would never stand up to something like a full Bathurst race, or the Le Mans 24 hour race. Very big difference between a 1/4 mile back yard hot rod engine, and a serious professional long distance endurance race engine. Why do you suppose there are no long stroke Formula One engines ? Given a choice, big bore short stroke is a better lower stressed package. The biggest weakness of the RB30 is its long throw spindly uncounterweighted crank, and the torsional vibrations it produces. The shorter throw RB25 and RB26 cranks are far stiffer because of more main/big end journal overlap. So yeah, the RB30DETT makes a great street and drag race engine, just don't confuse it with a thoroughbred professional race engine. The 2JZ is a better long stroke DOHC design simply because it was originally designed for high performance, the SOHC two valve RB30E and the later RB30ET were not.

Go back and read my post #204 I explained in great technical detail the problems of installing a solid cam in a hydraulic motor, and why it simply is not going to work. The fact that a great many of you just did not want to know any of this, is unfortunate. That others were talking only about how cool a really lumpy erratic idle sounded, and probably having wet dreams about that video clip of a vibrating exhaust tip, is absolutely hilarious. Sarcasm maybe, but personally I enjoy driving my car, I don't sit behind the exhaust tip jerking myself off because of the sounds it makes at idle. If you don't find all of that extremely funny, you should really take a long hard look at yourselves.

Sure, it is a very worthwhile upgrade. That is, if your only aim is a lumpy unstable idle, loss of low end torque, diminished fuel economy, and about 1/2 a Kw improvement at the extreme top end. But hey, if you guys only want a hot SOUNDING engine, instead of something that is actually more powerful, and you are having fun, go for it...

R32's are getting pretty old these days. And the chances are, that the car was first thrashed in Japan by the original owner, and then thrashed again by the last two or five previous owners here in Australia. Let's be realistic. People do not buy a GTR to putter around at 50 Kmh, and drive to the bowls club twice a week, then to cash the pension check on Thursdays, and then to church on Sundays. The bloody thing has been clutch dumped at 8,000 RPM hundreds of times, and probably seriously pranged a few times too. A really tired R32 GTR is going to be a money pit. If you want a cheap to run and reliable GTR with no problems, get a mint condition low mileage R34 GTR, if you can find one. R32 GTR's are cheap for a reason..............

A 450 Hp turbo will indeed supply 675 CFM at 1 bar boost. The compressor flow map will confirm that if you look.

It has absolutely nothing to do with engine power. The standard method of sizing turbos used by Garrett and most other other turbo companies these days, only refers to the compressor airflow. If you look at a compressor map, and draw a horizontal line at a pressure ratio of 2.0 (14.7 psi boost). You then move along that line into the choke region at the right, until the adiabatic efficiency drops to 60%. The airflow figure that the turbo can produce one bar of boost at 60% is the airflow rating for that sized compressor. You then assume 1.5 CFM per horsepower to turn that airflow into horsepower. You then know that a 300 Hp turbo can supply 450 CFM of air at 14.7psi boost with an adiabatic efficiency of 60%. It may produce 300 Hp on a real engine, or it may even produce a lot more than that at much higher boost pressures. Or a lot less power if the turbo is not well matched to the engine. It is just a very convenient way of comparing one sized compressor to another size of compressor by measuring both under exactly the same operating conditions.

How much gain ? Well that depends on where the cams are to begin with. By doing a twin cam conversion on an RB30, the cam positions could both now be miles away from what it was on the original engine. It is a meaningless question. Like saying I am now completely lost, how far is it EXACTLY from here to back home? The very first thing you should be doing is very accurately measuring the exact valve opening and closing points with a dial indicator and a degree wheel. Then, if the cams are not where you want them, use adjustable cam gears to move them to where you think would be optimum. How much lost power you can recover depends on how far out the cam timing is to begin with.

Wear out.... High mileage, bore piston and ring scoring from lack of air cleaner or contaminated oil. Failing to seal.... Not run in properly, excessive ring to piston groove side clearance, rings gummed up in piston grooves due to sludge and varnish from crap mineral oil, excessive piston rock caused by use of unsuitable forged pistons. Broken rings.... Ring gap too small, detonation.

Just check with a multimeter the voltages on the air flow meter you have now. Only four pins, two should be ground, one has +12, and the other a small signal voltage. They will either be the same, or different. But either way you should be able to figure out where the wires should go without too much trouble.

Actually if you look at the orange sticker on the Z32 air flow meter, it says made by: UNISIA JECS Corporation, Made in Japan. Nissan just buy them in, like many other parts in the car.

What a dumb question. Rings are made from metal, and metal can never be alive. So you can never kill a ring if it was never alive in the first place. Do you mean break, wear out, fail to seal, or what exactly ? If you ask a proper question, you will quite likely get a proper answer.

Don't know about GTR wiring, but I can tell you about Z32 pin connections. There are provision for six pins, from left to right looking at the connector they are A to F. some Z32s only have only four pins, with the two end pins missing or blank on a standard six pin Bosch connector. A/ no connection, the pin may not even be there. B/ output signal, about 0.5v no flow, to +5v max air flow C/ signal ground, usually connected to screen of signal cable going to ECU D/ power ground E/ +12 supply from ignition switch F/ no connection, the pin may not even be there.

All the mesh does is break up big incoming swirls and eddies into small swirls and eddies. If your airbox and upstream pipework is reasonably well designed the mesh does absolutely nothing. Removing it offers no advantage. But on some cars, the air flowing into the flow meter may do funny things at certain particular speeds and loads. Removing the mesh may therefore sometimes cause some strange problems to arise that were not there with the mesh fitted. But not on all cars.

Try again and be patient a while longer. He maybe away from the computer as he runs a pretty busy business these days.

Well that all depends what you want !!! He makes them to order, and can provide whatever you ask for. Hi mount, low mount, choice of turbo flange, with or without external wastegate flange. Lots of different possibilities for a Skyline. But a six cylinder with external wastegate might be in the region of just over a grand. Better to ask 6Boost for a quote.

I too can recommend 6Boost's manifolds. Excellent manifolds, and a top bloke to do business with.

Fit an RB30 bottom end under your existing cylinder head. Or fit a supercharger.