Any time you reduce static comp ratio, you decrease economy.

Although technically driven sedately the addition of a turbo shouldn't be a detriment - I dare you to find one person on the planet who has fitted a turbo and then doesn't drive it hard most of the time, to the point the economy isn't worth writing home about.

Another angle to consider - with typical 4sp and either the 3.9 or 4.1 diff - relatively the motor is screaming at highway cruise (esp if you sit on or in some people's cases over, the posted limit). If you hypothetically swapped in 3.7 or even 3.5ish diff gears, the reduction in freeway rpms for any given roadspeed will likely give you a 5% improvement in fuel economy. Since the engine is boosted, it'll have far far more torque on tap and the change in diff gearing still means more torque at the wheels. You could even go further and say that it's hard to get max boost in first gear, you flash to redline and don't use it. Will taller gearing, you spend more time in first, spool the turbo, and actually get to 'use' some of first gear with decent boost, and believe it or not (and turbos are the sole exception here, it doesn't apply to supercharging which has to lag or spoolup issues, never has never will) you can end up with a car that is quicker 0-100km/h with 3.7 gears and turbo than with 4.1 gears and turbo. Of course it's all application dependant, but the above scenario is indeed possible.

looking at the dizzy, it appears to be hall effect, that would mean you could (if the existing one died) run the module from a blue motor commodore (vc-vk models) - as they are compatible (I know this as it's what is done to convert chyrsler electronic ignition, which is electronically triggered, but points spec coil is used, to hei ignition with an uprated coil and spark output.) You'd have to run the wires to it yourself, but that's no biggie. Generally the module is the only thing likely to ever die on that type of dizzy, and even then it can take a decade or more easily.

do you have a good condition uncorroded timing cover?? If so how much?

PM sent abt the axles

Here I was thinking I might be the only one into mopars as well! I don't suppose you could get a ballpark she'd want on the two vc sedans, and a quick once over as to their condition?

please put me down for one to suit a h165. Can make deposit any time after new years, let me know how much for a deposit and where to send.

If I might also ask - is it possible to order a second set of internal gears on top of the 'standard' option of a complete centre/carrier, and if so, how much extra above the $1100 odd for the centre in the first place? I suspect it will be expensive, given the amount of machine work necessary to make the gears, but thought I'd ask anyway.

maybe you should have read the lot - seriously.

The racing is murder analogy does not in -any- way translate. Everyone out there goes through medical tests, various stages of scrutineering, the rules are set out and safety is a big big deal. That said, EVERYONE out there is aware of the risks and takes that on board when they race. They are all consenting to the potential risks. That's a far cry from going out on a public road and just saying 'well everyone else out on the road, tough luck, I'm making that choice for you' It's not a nice thing that happened, but we can't look at it through rose coloured glasses and seriously expect any good to come from it.

If you read the whole post, you'd see that despite my misgivings about the actions that lead to this fatality, I did have positive things to say about what could be done in future to help prevent a re-occurance, and the benefits of having higher expectations from one another.

It's absolutely not ok that this young man died, but should we just ignore his own culpability in it, or _highlight_ it in the hope we can prevent another person following in his footsteps???

I'm absolutely ok with people disagreeing with anything I've written but please don't misinterpret a realist reflection to be sociopathic.

I think maybe there could be a middle ground of sorts here. For all those who say it's a callous and harsh to be down on the bloke who lost his life - let me ask you this - maybe just maybe had enough people drummed it into his skull from a young age that driving is a privelege and there's huge difference between taking risks, and putting _other_ people at risk, do you think MAYBE, he might have been a little less inclined to hoon on the street (and let's not kid about, we don't know exactly how fast he was going, but you would have to be nuts to think he was doing 50 and driving like there was an raw egg between his right foot and the accelerator pedal) - and he _might_ actually still be alive today? Is there a possibility that the feelings of those who say he brought it on himself and who don't mourn his loss might actually have the very perspective/school of thought that might have saved this bloke had it gotten through to him?

I do think the bloke's death is a tragedy - without question. But if you were to ask me what I'd prefer - him dead and nobody else, or him to scrape through but another innocent bystander to get the slightest tiniest injury (let alone them dying) then I'd have to say (without hesitation) that his death would be my choice. If I had a carte blanche choice, I'd choose that he never had the accident, and nobody, himself, the passenger, innocent bystanders etc were killed or even harmed at all. But this is life, not a saved game on xbox.

We should realise that as tragic as the death is, this bloke was a murderer. He murdered himself. Or at the very least manslaughter. There's intent, pre-meditation, knowledge of the danger. Don't just imagine what it would have been like if he hit a child in the street and killed them. What about if he hit a child, and they survived, to spend the rest of their life a quadraplegic, their parents unable to provide them with _any_ quality of life (at least of the type we all take for granted) - being powerless to give back to their child what was stolen mercilessly. That'd be hell on earth. Forget this notion of 'closure' it's a myth propogated by talk shows and the like. Such trauma (esp if it's in their face every day thereafter) is profound and almost limitless in the despair it can cause. Nothing in the world could be said that would somehow make up for that, and it's precisely what the young bloke risked when hooning in an unrego'd car on a public road, in a suburban area.

Either we all keep group hugging and not attributing blame to anyone, or we start getting our gonads out of the grip of the politically correct and confront the reality of dangerous driving and risky behaviours. If this guy had done it on some deserted stretch of road somewhere, or in a factory area at night, whatever, I'd not have any objection whatsoever as to his behaviour.

I'm not suggesting I was a perfect angel when I was younger (and at 36 I'm not even close to that now, and nor will I ever be) but the things I did in cars which might have been in pretty shady territory legally, were nowhere near where anyone but myself could get hurt. furthermore, the stupid things I _did_ do - I had a win it or wear it attitude. If I did something foolish in a car (or got into some foolish confrontation that I could have walked away from) and I got egg on my face, I wouldn't be shaking a fist at the sky and claiming I was hard done by.

People, esp those that have had licences for only a few years, do die on the roads, and far more so than anyone would be comfortable with (there'll never be a zero road toll, but it doesn't mean we shouldn't aim for it), Either we get serious and more to the point firm about people driving like imbeciles (and I mean that in the general sense, not specifically to the young bloke who lost his life).

At the same time as getting hard on idiots, I wholeheartedly support the option others have raised - namely to get the government behind (if it can't be financed under its own steam without being too expensive to be accessible to those it's supposed to be helping) extra nights/weekends at dragstrips and other race circuits for all sorts of entry level, run what ya brung stuff. I'm not delusional enough to believe that even with such activities a few times a week that some idiots won't still be idiots. They will, but then when they wind up in court, they can't cry crocodile tears, play the victim and make out they had no other legitimate or affordable outlet for their passion/hobby.

People talk about the Datsun community, or family. Well one of the most important things about family (or should be) is that there should be a concerted effort to nurture in the younger siblings a sense of responsibility and discipline and ethics. Not just a 'well you are family, you can do no wrong' stance. There are even those families who stand up for their family members who commit atrocities like gang rapes. Now nobody is suggesting anyone here is a gang rapist, but you get my point. Maybe if those family members had raised their male sons to have respect for women, or whatever the scenario, they'd be less inclined to take such things for granted as if it was no big deal. I've said it before and I'll say it again - there's a chance that this poor bloke might actually still be ALIVE, if enough people had drummed into his head beforehand just how inappropriate driving an unregod car at speed on a suburban street was. To the passenger, I don't mean this lightly either - but I'm not sure I can take your word for the whole situation 100% at face value, and my reason for this is twofold - 1. you are his best mate and have just gone through a very traumatic event, and more disturbingly 2. you _chose_ to get into an unregistered car with him whilst he did what he did. I am _extremely_ relieved that you got out of it alive and well (physically) and I wish you a full and speedy recovery emotionally (I can't imagine what you are going through, and don't take that comment lightly). I would _hope_ that you might seize an opportunity to have some real good come out of this. I know the media is a parasite/vulture in general, and they'll likely twist and edit anything you say, but give it a go at writing to them, and your local government, and see what you can legitimately do to bring awareness to the issue, and perhaps prevent anyone else going through it. I'm not talking about their knee jerk speed limit or traffic island nonsense, but real change, push for driver education and the like. It certainly can't hurt to try.


For my own feelings, I must admit I am selfish enough that I am concerned that enough incidents like this, and sooner or later we'll have a situation where all car modification is illegal, and hoon laws end up making it impossible to enjoy our hobby. I'm sick to death of having to alternate between 50 and 20 km/h to go over 40,000 odd speed humps in local suburban streets. Extra stress on the brakes, the suspension, extra fuel consumed. Without the speedhumps I would have stuck to any reasonable limit. Now it's just crazy.

I'll try and offer some responses to the points raised. I'll say at the outset, I'm not the best writer in the world, so if any of this comes of as being any way negative or something, please attribute it to my communication skills, and not to any attitude or arrogance or anything on my part!

The case of the GTR skylines is a good one to raise. It might be worth noting that as raced at one point in Aus, they did in fact add water mist spray to the brake discs, as that (in this very specific context) was capable of far greater cooling than all the available air going to the brakes. It's also worth noting that the added problem is the brake discs reach their hottest temp (obviously) at the end of a long braking distance, and at the same time, the airflow under/through the car and hence brake discs gets lower and lower, due to the car slowing, so the cooling available drops.

The reason I add this tid-bit is that the air-air intercooler will be in exactly the same boat for the first portion of any acceleration run, where airflow through the fins would be lower. Thankfully the turbo has just started outputting higher temps and there's some mass of alloy in the intercooler body itself which will take care of some of the heat until the car picks up more speed.

Certainly if you ran a dry ice/coolant reservoir (let's say for argument's sake it's just an esky sealed somewhere so no CO2 gets to the cockpit or anything!) _eventually_ you will get to the point all the CO2 is gone, and the coolant temp will rise. But this will take _ages_ (in racing terms).

The thing is, volume for volume at room temperature and atmospheric pressure, water has about 200 odd times the density/mass of air, and as such 200 times the heat transfer ability. Meaning a relatively small quantity of it will still take a while to heat up. There's a reason cars use water/coolamt for their main cooling system, it's just so much more efficient size for size - look at some old air cooler VW motors, and the static comps they can and can't safely run on pump fuel vs some water jacketed engines of the same era, and the vws also run oil coolers as standard to help cope)...The cooling system is of interest because it deals with the heat of _combustion_ that isn't successfully harnessed and used to turn the crank (and even modern engines aren't all that thermally efficient) - which is a truckload of heat, with an intercooler we are only dealing with the heat which is a byproduct of the _compression_ of the air by the turbo. Relatively speaking less heat to deal with, and therefore not requiring a massive amount of water to work.

There are still of course inefficiencies with water to air, but it's not a dead loss.

About the best demonstration I can think of to show the effectiveness of water to air is to get a piece of steel bar, and heat with an oxy till it's bright red. Now place the biggest fan you can find on it, a few if you have them, and time how long it takes to cool to the point it can be handled without gloves. Now repeat the heat up process and drop it into a bucket of water, and it'll be done in seconds.

Yes, the water might _eventually_ (for sake of argument) reach 100C. At which point it would have a change of state, esp at the 'hot' side and the intercooling effect would be stuff all. But let's consider an alternative - perhaps not drag racing, say circuit racing. Well instead of having an esky in the back with the dry ice, alternately there could simply be a second radiator, functioning much a car radiator, this one to take heat back out of the intercooler's coolant circuit. With this on board it could constantly be taking some of the heat back out. Now if it was properly sealed so it could retain pressure as the temp rises, the water in it would no longer turn to steam, and would still cool. The thing to remember is that even at 100C that water flowing through the core can still take a lot of heat out of the intake charge. It's not hard to have turbo compressor outlet temperatures well above 100C. Well above it. So it can still do a lot of work. And if the setup was such that the turbo compressor outlet wasn't a hell of a lot above 100C in the first place, then the water in the water to air intercooler would never get that hot anyway and would therefore always be taking heat out of the system. Additionally with the option of the radiator to cool the charge, that will effectively be cooling all the time there is any airflow through the core (to varying degrees). There's no racing in the world (tractor pulling is about the most brutal, and certainly an exception and you'll note that water injection is, if allowed, a big deal in that arena) where you are actually at full throttle/boost indefinitely. It's usually not more than 10-20 seconds at a time, and every time you are off the throttle, or just at lower/medium throttle, there isn't a lot of heat being produced by the turbo comrpessor side, so the water to air intercooler has some 'down time' where it can cool off to some degree for the next time the throttle/boost is ramped up. It doesn't actually take a huge radiator to allow sufficient cooling for this to be adequate to never overheat under racing conditions.

Further on the 100C water scenario - it's obviously no groundbreaking insight that the amount of heat energy required to raise water each 1c (as much as it is) isn't linear with that required to take it from 99-101C (I'm blurring the goalposts there for the sake of simplicity) - i.e. a change of state from liquid to gas (steam) is significantly greater, and a hell of a lot of heat energy can be absorbed just in the effort to achieve any substantial extent of change of state.

Some of the water to air cooling 'cores' (if you could call them that) have some decent designs as far as effectively transferring heat into the intercooler coolant medium itself. If you check out some of the online patents websites, there's a couple detailing 'laminova' water to air cooling. They use water passages with thin fins all the way around for maximum surface exposure with limited (relatively) disruption and restriction of flow. From reading what little I could on said patents, it seems they were initially conceived and developed for other cooling (I think transmission, but don't quote me) and someone took the idea and adapted it to intake charge cooling. Certainly worth a google search or two.

I'd also add that once you get to some serious boost levels, and of course the bigger the engine/boost level the worse it gets) the size air-air cooler being used is humungous, requiring bumper/grill/radiator panel surgery just to clear, and that carries with it strong risk of attention from the boys in blue, possibly rendering the car unroadworthy if any of the cut away areas are deemed structural, and also the increased risk of debris on the road damaging it, such is it's geater 'target area' for anything to hit it.


They aren't a 'free ride' and there are reasons I can think of that some if not many manufacturers opt for air to air intercoolers. The first would be simplicity/economic factors. Since they aren't paying the massive markup we end users would have to to have a single intercooler produced, they can fit the air-air quite cheaply. Important too is the fact that the air-air _does_ indeed work, and work well, certainly effective enough for typical factory boost levels. That said, it's no surprise that one of the first mods people look at on a lot of factory turbo/performance cars (beyond some really elementary stuff like freer exhaust from the turbo on back and perhaps the odd couple of psi) is a bigger intercooler, because the factory one isn't enough to cope with much more than factory boost levels.

There's also nothing to 'break' but the cooler itself. if it springs a leak, you'll likely hear it, or lose boost and the problem will be found, no harm, no foul (apart from core/cooler repair). If a water to air springs a leak, it could get into the intake. Probably not enough to hydraulicise (and under boost it'd be pushing air into the water to air, not sucking water into the intake). But without the water, they provide no cooling, so the first sign would potentially be a damaged engine. Same goes if the pump itself fails. Given this risk, no doubt more than a few manufacturers, wanting to idiot proof their new cars against some owners, try and take all the human error out of the equation. Similar to water injetion. As effective as it is, they wouldn't want to rely on all owners to monitor it, or even fill it if they used a warning light when levels were low, and the issue of the pump failure.

I can't speak for everone into older cars, but I think it's fair to say that there's more of a hands on ethic with such enthusiasts, so nobody here or in other car enthusiast groups of a similar nature would be the ones to neglect stuff discussed above and damage their engine with a water to air. But it's a different proposition to car manufacturers. Another example might be ABS. In an emergency most drivers will panic and jam on the brakes, locking them up, and in such situations, a skidding tyre has lost grip, so braking distances are longer. With ABS, in that situation, it would reduce braking distance. But the nature of how abs works means that if you hypothetically took a very highly skilled driver, who has practiced emergency stops and hypothetically won't panic when a real accident is imminent, if they applied the brakes, but were skilled enough to avoid lockup, and kept it all at the limit of the brakes, the stopping distances would actually be shorter than with ABS. Similarly on dirt/gravel, it's actually advantageous to lock up the brakes in some situations, as it starts to act like a bulldozer bunching up gravel in front of the tyres like a little wedge and actually improves the ability to stop. ABS in such a situation can be far worse. Now does this mean that ABS is rubbish? Of course not, it's just indicative of the fact that manufacturers have other priorities than optimal performance with a skilled/knowledgeable operator.

Having said all that, aside from cheaper air-air stuff coming in from China, many people here would be running relatively small engines, and so you can get absolute bargains by sourcing second hand air-air coolers from people with larger motors who are upgrading. Something like those off series 4/5 rx7s would work well. Around 2000-2001 they were available 'for a song' from many rotary workshops. No idea their availability or pricing more recently though!

I'm absolutely not suggesting air-air is worthless, just bringing up the fact that there is some real (and mostly unexploited) potential with water to air coolers. There was a time when lpg was considered taxi fuel and nobody here took it even remotely serious as having potential in performance cars. Now, it's a fairly well accepted fact (as it has been in parts of the USA/Canada). In other parts of the world where propane/lpg is in its infancy, you'll find many thinking 'you lose power' on lpg. Technically correct in some applications, but if a motor is built for it to start with, then it's not the case. Same goes for water to air - if it's poorly implemented, it's a dog, but done right, different kettle of fish.

On the topic of water vs intercooling, I'm a little cynical and think that some of the reason is that there's a lot more money to be made selling big air-air intercoolers (admittedly the price has come down with some of the chinese gear) so every workshop has their drag car 'flagship' with a huge air to air at the front.

Some people also worry that water can't 'work' since it's relatively speaking, so low tech. For sure you can get more out of a system with a variable rate of water delivery, but given the up front costs of a diy setup, it's pretty hard to justify much else when on a budget.

If I was going to go to an intercooler at all, I'd personally prefer a water to air, since they can be much smaller for the same overall cooling effect. With coolant and dry ice chips in the reservoir you can actually get a water to air intercooler to cool the charge below ambient temps, something that is physically impossible with an air to air.