Warpspeed

I was quoted $2,200 just before Christmas for an SM4 installation kit by Ray Hall (the Autronic agents in Queensland). I ended up buying the cheaper SMC, and an Autronic air fuel meter instead. I agree the Autronic is probably the best ECU on the market, and a brand new SM4 for $1,800 is definitely a bargain for someone.

Should make the minimum driving age 25. Anyone younger than that is just an immature child, psychologically unable to control a vehicle. Maximum driving age should be limited to 30. Keep all the physically incapable, geriatrics off the roads. People between 25 and 30 must have perfect 20/20 vision, be able to run a mile in under four and a half minutes, and lift their own weight above their head. An IQ test should weed out the idiots, anyone scoring less than 180 should not be allowed drive. That would sure cure the peak hour traffic jams.

How about fitting an oil accumulator such as an acusump ? That would offer some additional protection, without any disadvantages at a fraction of the cost of a full dry sump system. It will also keep oil pressure up to the turbos for a short time after the ignition is turned off. I have never used one, but it may be worth thinking about.

There are several negatives, the obvious one being the very high cost of the system for no real advantage on a street driven car. The biggest one is there will be more critical parts to go wrong, and if they do fail, it will cost you an engine. My belief is that a dry sump system for the street, actually INCREASES your chance of blowing an engine. Race cars are different, they get checked and looked over very frequently. Now tell me, how often do you check over your street driven car for leaks, kinked or rubbing hoses, weeping fittings, damaged drive belts, and so on ? You probably don't, do it every time you drive the car, but a race car sure will be checked every time. A proper well designed aerospace quality dry sump system is horribly expensive for a reason, and there is plenty that can still go wrong with it. Any failure will cost you an engine. THe factory oil system is simple, fully enclosed within the engine, and as totally reliable as anything can be. (R32 GTR oil pump drives excepted). IF you blow off a hose, or snap a drive belt, it is all over. You might be surprised how many people get into trouble just fitting an external oil cooler, or remote oil filter. A complete dry sump system is vastly more complicated, and it will require constant checking if it is to be reliable. That is the difference between a race engine and a 100,000 Km+ street engine. The race engine gets looked after with constant checking and rebuilds. The street engine does not. If you don't believe me, when was the last time you flushed out your brake and clutch fluid lines and replaced all the fluid ? When did you last dismantle and repack your universal joints with grease ? Nobody really looks after a street car. My guess is your dry sump system will develop some problem through neglect and that will be VERY expensive.

You absolutely MUST have a very large turbo and very free flowing exhaust for those big cams to work. With stock turbo and exhaust, back pressure in the exhaust manifold is going to cause massive reversion with so much valve overlap. It will be cranky and gutless down low, will feel reasonably good at very small throttle openings at higher Rpm, and will die in the bum completely when you floor it. As Nismoid says, it will throw the air fuel ratios completely out. I don't think you are going to be terribly happy with it.

Yo cannot remove, or reduce the sump depth on a GTR unless you also remove the front diff ????? Lowering the engine much is not feasible either unless you remove the flywheel and cut the bellhousing away. So forget about relocating the engine lower, it is just not practical on a GTR. So you want to spend several thousand dollars to install a dry sump that will reduce oil wrap around the crankshaft at extreme Rpm. Good idea, it might get you an extra 20 Kw at 12,000 Rpm. I bet I could get a lot more than 20Kw by spending SEVERAL THOUSAND DOLLARS on something else besides a dry sump system. Or maybe it is oil surge that worries you. We all know that stock GTRs suffer from severe oil surge. Dozens of GTRs blow up every day and seize engines, because they are a crap motor. The factory oil system is absolutely pathetic and absolutely must be fixed, yes ??? Why WASTE money on something that is totally unnecessary for a street driven car.

Interesting, You denigrate him because of his age, and call him all sorts of names, but when it comes to a stand up fight you run away like a wimp coward. Maybe he was more of a man than you will ever be. Probably a better driver too.

I agree, they have supported the older model Skyline for ten years, that is pretty much the standard for most companies. They would be selling very few new units these days, they are not doing it for fun, so why should they ? There are vast numbers of secondhand cars, and plenty of secondhand FC computers still around. Finding one secondhand is never going to be a problem.

I bought some fairkly ordinaly ones (not gold) at REPCO a while back, cannot remember how much they cost. But if they were terribly expensive, I probably would have remembered.

Forget about staged turbos, if the manufacturers cannot get it to work properly with all their resources, you or I have less than zero chance of making it work either. But staging a turbo and a supercharger has been proven to work very well. Nissan did it on a production engine, Audi did it on a production engine, and now the 2006 model VW Golf GTI in Europe has both a turbo and a supercharger fitted to it. I have done it successfully too, and Stocky is in the final stages of building a turbo + supercharger system on an RB30DE. So stay tuned...

What sort of exhaust gas analyzer do you use ? I have an Autronic that uses the usual Bosch wideband sensor.

Yeah, 14.7 is the best figure to run. You can run it leaner than that, but then you will need to open the throttle just a little bit more to maintain constant speed. The result is you end up using the same amount of fuel, but more air passes through the engine. Exhaust gas temperatures will be higher, and you gain nothing. Leaning it off even further can cause a lean misfire, as others have already said and actually reduce economy. If you can get and maintain 14.7 at light loads and cruise you are doing o/k. The next thing to do is start working on cold enrichment. A lot more fuel can be used than is necessary when the engine is warming up and still below correct operating temperature. If you do a lot of short trips around the suburbs, this can kill economy, even if you drive like a granny. If you can lean it off when cold, and it still drives o/k, that is one way to get something for nothing. I have an Autronic which has a lot more features than some other ECUs and have been fiddling for quite a while. It is possible to get small improvements in economy, but if the factory system is running properly, small improvements are all you are going to get.

You are forgetting the basics, power is proportional to AIRFLOW not boost pressure. The standard 350Z has a high compression normally aspirated V6, which is pretty powerful anyway. 4.5psi is still enough to crank out almost 400 Hp. Laugh all you want, but it also has massive torque from 2,000 Rpm where it reaches full boost, on all the way up to the redline, and virtually no lag with these new turbos. Remember it has almost an extra litre of engine capacity over a GTR, and reaches full boost at half the Rpm. It is an absolute torque monster in any of it's six gears according to peapole that have driven it.

If it is a standard rebuild to basically stock specifications, the only requirement is good workmanship and care. Nothing particularly different or difficult to any other engine. If a lot of non standard parts are being used, it is a completely different situation. Many genuine racing parts are simply not suitable for a long life road engine. Special engines require special care and expert knowledge in selecting and fitting non standard parts.

Agree with Wink. These cars are awsome, but they are known to have relatively weak gearboxes. If it has been thrashed, budget for some fairly expensive gearbox repairs. It is a fairly common problem.

Both you guys are both perfectly right of course, but the method I described is the official one used by Garrett. The only way to make any sense out of any of this, is to get a compressor map and plot where you are.

The way Garrett and most other turbo manufacturers rate there turbos is as follows. They run up the compressor until the pressure ratio is exactly 2.0, that is exactly 14.7 psi boost. They then steadily increase the airflow up past the efficiency peak until the adiabatic efficiency drops back to 60%. You can do it yourself by eyeballing a flow map. Draw a horizontal line at 2.0 pressure ratio, and note where it crosses the 60% island on the map in the choke region (to the right). Then drop a vertical line down to indicate flow. Engine power is assumed to be one Hp for each 1.5 CFM at that operating condition. It is just one standardised operating point on the whole flow map to very roughly compare one compressors flow capacity to another compressors flow capacity. An actual real engine may operate a long way from both 14.7 psi boost, and the 60% efficiency point on the map. But it is still a pretty good average operating point to choose. The exhaust turbine flow, or back pressure, does not come into this at all, but is also extremely important for the engine.

Well, you could always try it and see. Many people do run waste spark successfully without any problems as stated above. But why bother ? The SMC has six independent ignition outputs already there. So why not just use six standard Nissan modules ? That is the ideal setup and it is so very easy to do.

Two ways to tackle the head bolts. 1/ Drill and tap the block to take the 12mm GTR bolts, (that can be tricky). 2/ Use a set of 10mm standard RB25DE head bolts. They fit the RB30 block and are the correct length for the GTR head. The GTR head fits straight onto the Rb30 block, and the dowels align the head and head gasket. The bolts only clamp down the head, they don't locate anything. Either 10mm or 12mm bolts work fine.

Better idea would be some flanges, steam pipe bends, box of welding rods and a slab or two of beer. by the time the beer is completed, so are the manifolds. That works for me.

Yes GT-ZZ is the new replacement for the 2530, but it has not been released for sale yet. I have heard that a pair of GT-ZZs on a Nissan 350Z engine spool up to full boost (4.5psi maximum on that engine) at only 2,000 Rpm. For size they slot inbetween the GTSS and GTRS. The HKS dealers do not have them yet, but it won't be long.

Dyno 2000 is American, so they still use the imperial Hp and Ft/Lb. 210 Ft/Lb = 285 Nm

Sure it runs o/k with wasted spark. But how do you know it will not run a lot better with a properly timed ignition system ? Firing the plug during the beginning of the induction stroke is NOT a good idea. Firing it during the end of the exhaust stroke will work fine. What is actually happening in the combustion space during plug firing depends very much on valve timing, ignition timing, injector timing, and relative boost/exhaust pressures. Think about it. Talk to experienced engine builders and engine tuners, read some serious books. Wasted spark runs perfectly well on some combinations, but simply will not work at all with other engine combinations. You don't have to believe me. But if you think it all through very carefully, you may begin to see some potential problems that you may not have been previously aware of. A turbo engine with very high total exhaust back pressure will be much more tolerant of waste spark, than a highly supercharged engine with open exhaust.

I agree. But suppose a guy was building an RB30DET for his VL Commodore, and had no ignition for it. He COULD use a set of standard Skyline modules, or he could do something quite different. Six Bosch modules plus six XF Falcon ignition coils ($10 ea), about $1,000 An Autronic CDI and three, or six, ignition coils, again maybe $1,000 Six (brand new ?) Nissan ignition modules, $ ????

They don't have closed loop idle, simply because 14.5:1 is usually far too lean for a stable idle, and that is all you are going to get with a narrow band oxygen sensor. But there is automatic closed loop idle speed control available, and separate fuel and ignition maps for idle that allow for water and air temperature correction, as well as battery voltage correction. (faster idle with flat battery). There are also time functions that can be set for idle enrichment. The whole idle thing can be set up to work wonderfully well without closed loop. Closed loop operation (for highway) is available if you wish on a basic SMC. It requires fitting a narrow band oxygen sensor and just enabling the closed loop function. You can have it run either closed loop, or open loop, at any location anywhere in the fuel map. So you can set it up any way you want. In closed loop you only get 145:1 which is where the oxygen sensor switches from rich/lean. But if you choose to run it open loop you can select any air fuel ratio you want. It will run at 17:1 without any problems if that is what it is set to. I run my SMC open loop set to 14.7, and that is exactly what it runs at. No real need for closed loop, but it is there if I ever wanted to try it.