Interesting Write Up - GTiR

Mad

Well-Known Member
http://www.oocities.org/evilnis_nz/f_a_q.html

NISSAN PULSAR GTIR F.A.Q
Q :Can I change the timing?
Sure can. There's a small nut on top of the distributor (mines sealed with tape). Take the tape off and slacken off the nut. The distributor should now be free to move a few cm's either way.

Q: Where the hell is the ECU?
Its right in the middle of the car, under the dashboard, at floor level. Looking in either footwell, towards the middle of the car, there are small plastic blanking plates on either side of the centre console. Remove these, and the ECU is right behind lying flat. Its a real pig to work on!

Q: ....and where is the ABS computer?
The ABS computer is under the left hand kick panel in the passenger footwell.

Q: Whats the capacity of the fuel tank?
50 litres unleaded/super unleaded (min. 92 octane)

Q: What oil have you tried/would you recommend? How much does it take?
Last question first : 3.2 litres (3.4 if you include the filter) .Nissan recommend a 5w 30 oil, changed every 5000 kms (thats 3100 miles).Personally I use Castol
Magnetec,which is a 10W 40. I'm never too keen on these thinner oils, they do offer better protection at startup, but arguably, if you idle your machine properly you shouldn't get any problems at startup. Mobil 1 is a definate no no for me. I saw too many turbo'd engines blow up, which were attributed to this oil. Fair enough running Mobil if you've got a fully re-built comp. spec. Group A blueprinted engine pushing out 400+bhp, but i'm running around in a 260 bhp engine thats done 64000 miles. Not quite the same. Aside from the obvious (use branded before it's too late, and change it as frequently as you can afford) there is a debate raging on another site about what to use for turbo's. If the oil you want to use meets the specification in the handbook, you should feel confident that it will perform. If you're buying an oil on a mate's advice - can he/she prove that the oil won't damage your motor? If in doubt - ask your local Nissan dealer. I hear that fully synthetic is a no-no for turbo's. Anyone confirm this?

Q: How much water does it take?
It takes 5.7 litres of water, of which you should reckon 25% or 33% should be anti-freeze (depending where you live). Never put too much anti-freeze in an engine. It actually corrodes the alloy head if used to excess.

Q:What size speakers can I get in the car?
The fronts are (correct me if i'm wrong) 7" x 5" ,possibly even smaller, and sound poo. My car's got Kenwood replacements of the same size, which dont sound too bad, but lack bass. I've heard of people having limited success with 6.5" speakers, the main problem with fitting is the odd shaped hole behind the speaker ( a sort of squashed circle), but it is possible. Rears are standard round 5" jobbies, fairly easily available.

Q: Does anyone know what the warning light on the right of the instruments in the middle means?
Its the light warning of high exhaust temperature in the catalytic convertor. The is a danger of them catching fire if temperatures remain too high for too long. How you've got it to come on, I have no idea.I've pulled a Volkswagen Golf up a 1 in 4 hill (25%) with high oil and water temperatures, and the boost gauge reading high all the way up - I never had this light come on though. I'm guessing, but maybe the lamda sensor doubles as a thermistor of some kind?

Q: I can't understand the boost guage!
The standard boost gauge in an imported GTiR is in the unit Torr, or millimetres of mercury. Standard boost, approx 9 - 10 psi , will give a reading of around
5mmHg. Just over 7mmHg is 1 bar.Bar is the metric standard for pressure. 1bar = 14.7psi roughly. Always bear in mind that the in car guage is reading boost AT THE ENGINE i.e. the inlet manifold. This is after it has passed through the restrictions of the intercooler and throttle bodies. A turbocharger manufacturer will always quote the maximum boost the turbo produces (say 15psi) FROM THE TURBO. A loss of 4-5psi is expected between the turbo and the engine, hence the in-car reading would be somewhere in the region of 10 psi or 5mmHg. UK cars have a gauge in psi as standard.

Q: Whats the blanking plate for, behind the gearstick?
Some Pulsars were fitted with heated front seat, and this is where the switches would go. Does anyone actualy have these!

Q: I give up, what are the small hooks for on the carpet in the front?
The Japanese foot mats, of course!

Q: Wheels & tyres
Generally 7" x 16 or 7" x 17 maximum, but if you want to roll the arches (the arch shape "L" becomes a tight "J" and you'll probably muck up the paint, (I hear it's possible to persuade the lip of the arch into the right shape with a wooden baseball bat! I won't be trying this) then you might go to 7.5" x 17 or even 8 x 17, but then you may run into clearance problems with the inner arch. Tyres are a moot point: generally, tyres that are good in the wet are not as good in the dry (e.g., more wear) and tyres that are good in the dry are usually hopeless in the wet. No tyre is "the best" at everything. There may be an excellent compromise tyre, but is it too expensive for your budget? Also, in the UK, it is rare for the air temperature to rise over 30c. On the two days a year when that happens in the UK (like 1998) a certain tyre may give the best 'bite' and 'feel'. It's more likely to snow than that. If you do track days, get a pair of spare rims, check the weather forecast (hahaha-UK only) and kit them up with suitably grippy low-profiles. More debate on this one I feel certain! I run 7x17" wheels with 205/40ZR17 Falken GRB tyres all round. The only wheel that rubs is the front nearside (passenger side) for some reason. The point on the arch that it rubs against is the mounting screw for the arch plastic. The solution is, indeed, a large hammer.

Q: How much boost can I run?
The more, the less. That is - it depends what you want to do with the car.If you're out to post the fastest time on a drag strip and can afford a rebuild afterwards, then I've seen figures of 450 BHP from a well overboosted car. That owner has gone through a couple of gearboxes, too.Standard boost is 9psi and if the usual engineering tolerances are built in,then up to 10%extra might be acceptable for everyday use, hence varying 'standard' boost quotes up to e.g., "about 10.6psi". You pays your money and you takes your chances.

Q: How low will it go?
-35mm is probably as far as you'd want to go for everyday use: but check first that your car hasn't already been lowered! After that - it depends on whether you want to use all four (five) seats at the same time. A simple check to see if your car has been lowered - take one baby elephant, and if you can fit it under the arch, your car hasn't been lowered! Seriously, though, it also seems that if you use springs designed for the Sunny (N14) body in general (i.e. all models), you can get a good 70mm drop on the front. The back, not so much , maybe 45mm. But this is good if you ever need to carry any passengers!

Q: What are the best geometry settings?
Horses for courses - go radical and buy tyres twice as frequently as you should. That is, too much camber (positive or negative ) will give unevenwear. So will too much toe-in/out. But if it's for the track - you'd want the settings that give the best performance and to heck with tyre wear.Anyone out there help, please, is it necessary to change settings? If so,why?

Q: How do I keep my wheels looking like new?
Oh no! My wheels got dirty. Sorry, but for me there's more to life than worrying about minor scrapes and smudges. If they're originals and they're bad you can get them re-manufactured at almost any wheel/tyre outlet (they'll forward it to one or two specialist wheel restorers): the current price is about GBP35-45 (GBP = Great Britain, Pounds). I've seen some that have been done like this and it seemed to me that a lot of meat was taken off, making the rims more susceptible to further damage. Note that some tyres have a built-in 'shoulder' to help prevent damage.If you must use a toothbrush to clean them, here's what works for me (every 2-3 years, I really hate this work). Wait until they're cold. Clean them out of the hot sunlight - it just makes life easier. Wash with a wax-free shampoo: not a washing up detergent - that will seize your callipers. Don't dry. Rinse and agitate with a nylon bristle brush. Dry. Remove tar with a proper removing fluid. Use Wonder Wheels or a similar product, as directed. Wash again. Dry. Wax - no, seriously! But don't spray the wax, drop some onto a rag and rub vigorously. Buff the polish off and that's about the best you can do. (Colour Magic is good e.g., black for dark-pained wheels,because it has a slight de-oxidising effect. That is, it takes a layer of paint/lacquer off ... not enough to make any difference to the paint but a big difference to the finish). I would never use power tools to do any of the above. Maybe toothpaste works, I've never tried it but I hear it will make your wheels smell better that your average polish.

Q: Should I keep using the climate control in the winter?
Yes. It keeps the pump seals lubricated.

Q: Can I run leaded petrol?
One has to ask why, but yes you can so long as the catalyst and lambda sensor have been removed. If you live in the UK, removing a catalyst is illegal. This may be true in your country, too. A lambda sensor will rapidly fail if leaded fuels is used. A failed sensor will cause erroneous (possibly catastrophic) fuelling in your engine. Still want to do it?

Q: What's a turbo timer and must I use one?
Last point first: no. You can go without a turbo timer but after a period of on-boost running, wait for at least a minute before switching the engine off or else the turbo will be damaged by oil overheating in the bearings/shaft. You can guess from this it's the purpose of a turbo timer to automatically prevent the engine from being turned off and avoid consequent damage to the turbo. Note that it is illegal to leave a car unattended with the engine running, even if it's locked, in
NZ.

Q: What's the best alarm system?
How about a very big, angry dog wearing a bullet-proof vest? It'd make me think twice! Seriously, there's a golden rule about theft of any kind. Thieves, if they want it, they'll get it. The better systems give you a chance of getting it back at some later date e.g., Tracker. The better the (non-canine) system, the more it will cost. Currently, the Disklock is popular in the UK. It fits over, and completely covers, the steering wheel. My insurance demands a Thatcham (Association of British Insurers) Category 1 Alarm plus Immobiliser. That, to me, is the bare minimum I'd contemplate. With a rare (and getting rarer) model like the GTi-R all spares are hard to get, legally. And like any work of art they have a relatively high price on the street. Shame, but that's just the way it is. There's a popular story about a high-performance car that the owner parked in his converted garage - in pit lowered by a four-poster lift, all locked up. He'd had the work done because he was fed up with it being nicked all the time. One morning he went out his front door to see the car parked outside his house. With the keys on the driver's seat. The tealeaves did it just to prove that it could be done. I've got a Clifford Concept 50 CAT1 alarm/immobiliser. These are the very best alarms on the market, and come with a lifetime warranty.Thieves will literally walk away, cause its just too much trouble to steal. Clifford also give you GBP1,000 if your car is stolen with their alarm on board.

Q: Can I replace the standard catalyst with a high-performance one?
There have been no reported problems with doing this. All British vehicles registered AFTER August 1992, must by law have a catalytic convertor fitted. Vehicles registered before this time are allowed not to. HOWEVER if it is fitted it must be tested! Have you rang Nissan recently to find out how much a replacement is? 334GBP. Makes it worth while changing it out for a straight through pipe, at only 75GBP, doesn't it.

Q: What's an extended warranty and must I have one?
Last point first, again: no. But if you don't get a warranty and the starter motor goes you could be facing a bill up to four times the cost of the annual warranty
premium. That's what an extended warranty does - it covers you against certain unforeseen expenses. So, it's another form of insurance. Warranties generally
exclude items that are subject to "wear and tear" - like exhaust, brake pads and clutch. There are usually limits on claims, too. For example my policy covers me for up to GBP1,000 per claim and no more than GBP3,000 in total. Check the list of excluded items before you buy the cover and judge for yourself whether it's worth it. There are a number of national and international organisations providing extended warranties. A warranty of this type usually requires that the insurer arranges an inspection: it's to cover shed's being covered then huge claims being made.

Q: Whats adjustable on the suspension ?
The Gti-R is almost unique in that EVERYTHING on the front of the car is adjustable. Set-back, toe, castor, camber is all adjustable, but can cost a lot to do at a garage that charges per adjustment. Best to find a garage charging by the hour. The rear of the car loses out somewhat, as camber is not adjustable. As a rule lowering springs for our cars do not lower the back as much as the front because of this.

Q What should I do if I have to cross a flood/ford?
On the clutch housing, there is a rubber plug, after driving through water that is over the height of the housing (not very deep if your car is lowered), then you are supposed to remove this plug to drain [everything] off, then put the plug back in. This is from the Nissan handbook that comes with the car!

Q How can I get a Workshop Manual ?
Order part numbers Part # SM1E-1N4BG0 (Vol 1) and SM1E-2N4BG0 (Vol 2) In Australia get workshop manuals from Bookworks in Sydney. This mob is the supplier for all Nissan manuals. Contact: Bret Shadwell 56 Bonds Road, Punchbowl NSW 2196 Australia Ph: 61 2 9740 6766 Fx: 61 2 9740 6591 Vol 1 - Aud$395 Vol 2 - Aud$295 (just mortgage the house) There is also a supplementary book which just covers airbags, airconditioning, seatbelts for an extra Aud$90.

Q Are standard brakes adequate? If not, what can I do to improve them?
It depends on what you define as adequate. What do you want to use your car for? Is it a full-out circuit car or a cruismobile? That's the deciding factor. How often will maximum braking be required? If the answer is "only in emergencies" then the standard brakes are probably "adequate". More than that and the question is more difficult to answer. Why? Well a bit of theory won't go amiss, first, in helping you to decide what to do. Few cars can exceed 0.8g deceleration. The limit is the tyres breaking grip (locking). Full braking from 120kph on a GTi-R generates enough energy to bring 2 litres of water to the boil from ambient temperature. This heat has to be eliminated. Nearly all the energy lost during braking is turned into heat in the disk. The pads heat up, of course but it is also their job to insulate the caliper from heat. A small amount of noise is unavoidable. Size matters! If the disc becomes too thin, wear will increase exponentially, because heat cannot be eliminated into and from the mass of the disk during braking. The disk overheats and stresses form in all components. As an example, the surface temperature of a worn, 4mm thick disk increases by almost 3 times that of a new 10mm thick disk. At a depth of 2mm below the surface the temperature can bu up to 800oC. The minimum thickness of a disk is indelibly marked on the outside edge. Final surprise: the disk melts during braking. Not much - but just a few microns under the surface, the temperature exceeds the melting point of cast iron. So how can the brakes be improved? Well, under maximum braking the load is transferred to the front axle, so the front brakes are the most critical. If you want to retain standard running gear the only options available are improved pad material and braking fluid. There are four major components of a braking system;- a) disc b) pads (or more
specifically, the pad material) c) caliper, piston(s) and seals d) brake fluid If you want to use the car on the track, you'll probably need to change everything, including your budget. i) bigger diameter discs inside bigger wheels ii) cross-drilled and grooved disks (ventilated, of course) competition pads that only work after they have need brought up to temperature (dangerous for road use) iv) competition brake fluid that resists boiling better than standard fluid v) lighter, open, multi-pot calipers in aluminium to get rid of heat and keep it away from the brake fluid vi) full stainless steel braided hoses Failures can be characterised in any of these components, however, catastrophic events due to high-energy use will generally only occur in either the disk or the fluid. Brake fade due to vapour lock in the fluid is usually progressive, so that just leaves the disks. Failure commonly arises from;- 1) poor fitting (over-torque/dirt on the braking surface/mis-alignment/no running-in/caliper movement) 2) incorrect theory (disk is too small/thin/poor design/non-homogenous/wrong mix/under-specified) 3) wrong or poor pad material (vitrified disk/excessive pad wear/scoring) 4) excessive wear/cracks (not checked before use) There are many other elements embodied in the brake system: the pad material can comprise up to 20 seperate components. Most surprising (to me, anyway) are the inclusion of marble and graphite! The discs contain 93-94% grey cast iron. Carbon, silicon and manganese make up nearly all the rest but there are 9 other elements which are mainly impurities of manufacture and are impossible to eliminate. Conclusion: generally, bad brakes are ones that are just plain being asked to do more than was intended in the original design or are not properly checked/fitted. A 1974 1.5 Golf weighing 780kg uses the same disk as a 1030kg MKIII - because they got it right for normal, everyday use.

Q Is the standard clutch ok ? How can I tell ?
Clutches are rated by how many kg's they can handle. A standard road car will be able to handle 400kg. Most NA 4 cylinder cars have 400kg clutches. A hypo 4wd car will have a stronger clutch because there is more weight to push around in the drivetrain. The Nissan Pulsar GTi-R has a standard 600kg clutch, this will and does feel heavier than a standard road car. Nismo make upgrades to 880kg and a special 960kg (almost a 1 tonne clutch). Also when upgrading clutches try and get a carbon kevlar clutch as these will last 3 times as long as the standard unit. I am upgrading and will be getting a real mix and match job done. 1 side will be copper for total grip, and the other side will be kevlar for a bit of slip. One other thing to note is that kevlar grips better the hotter it gets
.
Q Would you buy a secondhand car 'blind'?
Do all the usual checks first - Japanese log book/service record. And don't be fobbed-off, good ones have a full Japanese service history to back up the odo.
Clocking is rife, so buyer beware! Here's what one NZ list member has to say ... Some guy went over to Japan because of these rumours and went to an auction and watched and noted the cars the NZers bought, he got the original reg forms from the authorities over there and brought them back. He found the people that brought the cars and they did a TV show on it. One guy had a 90 Subaru Legacy RS that had 65000km on the clock and in Japan it had 155000km on the clock. Why do they do it? Because clocked cars are cheaper and about all that is available over here. Some places guarantee the odo reading and they have stopped winding them back, but it hasn't affected the price. Yep buyer beware, most people don't believe the odo reading anymore so that is OK, you just have to get the car checked for everything. The upside of this is that if the car is three years old (or 5, 7 etc) in Japan the owner has to get the car totally checked and every nut and bolt is replaced to meet their rules for a Warrant of Fitness ("shaken", see below). So If you get a car that has been through this situation you should be fine. Japanese cars are sold with "shaken" which is commonly referred to as motor vehicle registration, but is actually a series of taxes, tests and compulsory insurance that you must have to drive your vehicle on the road. It consists of a Safety Inspection, Compulsory Insurance, Weight Tax and Vehicle tax. It's like an amalgamation of UK MOT (but taken to a much greater extreme) and insurance. The "shaken" that comes with a new car is valid for three years, but must be renewed at expiration at an average cost of US$1,500. The Japanese enforce this rule with strict penalties. The "shaken" is renewable on a bi-annual basis for the duration of ownership of the vehicle. Consequently, most vehicles available on the used market are 3,5,7 and 9 years old as they are usually traded in or sold by the user when the "shaken" expires. Purchasing vehicles with 6 months or more valid "shaken" increases the value of the vehicle domestically and generally is more expensive than units with no "shaken" left.
 

Mad

Well-Known Member
Q The GTi-R uses a 4WD system called ATTESA - what's that, then?
Here are a few mails received on the subject ... Thanks to Dean Browne for the following;- ATTESA - Advanced Total Traction Engineering System for All-terrain Yep, thats what ATTESA stands for and thats what it does, except it is not so advanced. One thing to note about the ATTESA system in the GTi-R is that it is not electronically controlled. The R33 and R34 Nissan Skyline GTR have the Electronically controlled version of this but that system has the actual name of ATTESA-ETS. The R32 and ["luxury"] GTi-R Nissans have a mechanical system based on so called clutches GTi-R Rear Diff and front diff: It may not be called an LSD by most people but in fact it's design and function are very similar. The basic function of the limited slip diff is to distribute power to the wheel with the most traction. The GTi-R ATTESA set up is built to do this. The rear and front diffs have clutches in them (well almost), these look like a CDROM disc with the last 1-2cm of the CDROM bent out on an angle. These clutches work in a surprisingly easy way. When the person driving the car puts the foot to the floor so to speak there are a several events that happen. 1, The power to driveshaft increases. 2, The spider gears push the side gears away from the diff towards the wheels. 3, This increased load(push) causes the clutches to straighten and lock. 4, The lock increases the power to that wheel. (remember this happens to both sides of the car). What happens when a wheel loses traction, The clutch on that side of the diff will lose its lock and therefore power will be forced onto the other wheel. simple?? The centre diff on the GTi-R: There are 2 type systems used on GTi-Rs, If you own a rally version you should be able to see the centre diff underneath your car. If you own a road version the centre diff is actually incorporated inside the gearbox housing. The reasons for this are obvious as the rally cars may have needed to have the centre diff changed during a rally and the easiest way to do this is to have the centre diff on the outside of the gearbox. These 2 systems function in the exact same way though. I have heard stories about the centre diffs in the GTi-R about whether they are a fluid/gel based unit or just another locking unit with clutches. I don't know which one it is yet but they both do the same thing it will sense (not really, it's mechanical) the loss of traction and distribute power in the other direction. That is as simple as I can make it and about as much as I know at the moment. When I get more information I will pass it on. There is nothing really advanced about this system and most other 4wd vehicles have a very similar system. As for the 50:50 torque split, it well known that this split is best used on gravel or wet roads. Hope this enlightens some and helps others. Any feedback or other ideas about this system will be appreciated. The rally cars (Group A/WRC car not the homologation version) have an active centre diff (hydraulic clutch), just like a R32 GT-R. I assume they also had electronic control using g-sensors and wheel speed inputs. ATTESA is totally rear wheel drive until wheel spin is detected, then the centre clutch is engaged to feed torque to the front. ATTESA E-TS is the same but can also electronically control torque split between the rear wheels.The ATTESA 4WD system is not a true all time 4WD. The rear diff has a viscous coupling permitting both wheels to drive under power, if one looses drive it is then transferred to the opposite wheel locking the rear drive shafts as one, the front is a conventional spider gear diff with no viscous coupling inside thus power is lost when one front wheel loses traction, the front viscous coupling sits between the transfer case and drive shaft to the rear diff, which would allow a certain amount of slip to the rear diff. Drive from the gearbox is always available to the rear wheels through the transfer case. If 4WD was to be maintained all the time ie. 4 wheels truly under power you would not suffer from oversteer as GTiR 's do because the car would be pushed and pulled through a corner not just pushed. If you look at the homologated GTiR its a totally different ball game, as it is a true all time 4WD dependant on what diff and transfer case combination you choose. It had additional electronic torque split and controlled slip diff with an automatic rear torque releasing system. In race or rally cars all time 4WD is feasible as with wheel spin or lifting off one or more wheels during hard cornering you dont suffer from diff bind as you would in a road car. Hope this helps without getting to technical, (all this is out of the w/shop manual & the original FIA GTiR Homologation Grp A Forms) Finally (for now) from Anthony Dix ... I have been in contact with Protech Developments in Melbourne re the GTiR 4WD system. The Nissan WRC car based on the GTiR had an active centre diff under computer control. This car is far from the 'Rally' version available to the public. (i.e. your car.) The two versions available to the public (luxury and rally) had the same 4WD system: - viscous limited slip diff at rear - viscous coupling at the centre (passive) - open front diff .

Q I've heard about intercooler watersprays - what does it do?
The aim of the exercise \par is NOT to wet the intercooler. By spraying an atomised mist of water into the stream of air entering the scoop, this air is
"air-conditioned" by your evaporative air-conditioner,and is thus cooled to below ambient air temperature, effectively creating a wind-chill. An Australian turbo owner (non-GTi-R) has done tests with heat probes and found that a good waterspray (not a firehose!), plus airscoop splitter, will reduce the outlet temperature from a Subaru intercooler by 10% or 8 degrees celcius. This is horspower for (almost) nothing, and is also a really "cool" trick. A useful addition is a small LED which lights up when the pump (switched on by boost) is pumping.

Q How long will a turbo last?
Properly serviced - and that just means oil/filter changes regular intervals with the right grade/quality oil and a _proprietary_ filter (don't save pennies here it's not worth it and the Nisssan unit is cheap anyway) - expect between 75,000 and 150,000 miles out of the turbo depending on how it's used.

Q What's "matching", then?
It's a technique used in blueprinting any engine. Imagine two pipes of exactly the same diameter. Both have flanges welded on to one end (the other two ends are irrelevant for this example). They are made by different companies. Each company works to the manufacturer's recommended tolerances. And, there's "give" in the (four) mounting holes. Result - the pipes won't form a continuous uninterrupted flow inside. Solutions;- 1) make a jig to line both pipes uo 100% - and use it every time the pipes need to be reconnected. And make a new one every time you have to replace one of the two pipes. And the jig must be able to be used "in situ". Not very practical? 2) weld two or three "pegs" into one flange and drill the same number of holes (interference fit only) in the other flange. The trick is to mate the pegs and holes (my wife who is "helping" with my spelling can't stop laughing at this stuff!) so that the id of both pipes gives 100% flow. I did this with a Ford xflow twin 40's inlet manifold and it worked a treat. I did it by measuring (id-to-hole centre on one side, id-to-peg centre on the other). Nothing's ever 100% but 99.9785% is ok for me. A by-product of pegging is that it's a piece of cake to get a 100% fit every time, without fail. No matter how much of a hurry you're in nor how cack-handed you are - like me. This whole idea is not for the casual, one-off fit, mind. It will take ages to do it "perfectly" - especially for us amateurs. It's more suited to the repeated removal/refit or them as wants a "perfection" once ever.

Q What's a knock sensor then?
The knock sensor is basically a piezoelectric microphone. The ECU uses a knock sensor chip to provide a bandpass filter tuned to the knock frequency (unique to each different engine design). It then full-wave rectifies and integrates the signal to provide a level indicating knock. Typically two channels are used - one as a reference not tuned to the knock frequency which is subtracted off the knock signal to eliminate the (huge amount of) background noise. To further eliminate noise, the ECU uses the camshaft position sensor to only "listen" and the point when knock is likely to happen. All in all it's quite involved to get a reliable electronic indication. (You may see the "pings" on a digital oscilloscope though.) A stethoscope and a long rubber tube was the best solution. Harris Semiconductor make suitable chips, full details on: http://www.semi.harris.com/auto/engine.htm#KNOCK Their chips need a microprocessor interface to program the knock frequency. I've also seen teh "old fashioned" method - take any long screwdriver, put the sharp end onto any part of the engine you're interested in and put the blunt end on (not in!) your ear.

Q Can I add liquid power (additives)?
Toluene - see http://mail.odsnet.com/TRIFacts/36.html and decide for yourself! Methyl Benzene (aka toluene). If you take Premium unleaded as having an octane rating of 96, then a 10% mixture of Methyl Benzene will raise it to 98, 20% to 100 and 30% to 102. They [Shell] do not recommend a mixture of more than 30% due to volatility constraints.

Q What happens if I break down - how do I get it towed?
NISSAN recommends that the 4-wheel drive vehicle be towed with all wheels off the ground as follows: 1. Using a flat-bed truck. 2. Using a combination of a tow truck and a dolly. Towing with four wheels on ground, observe the following restricted towing speeds and distances. Speed: Below 50 km/h (30 MPH) Distance: Less than 65 km (40 miles) Never tow a 4-wheel drive model with front or rear wheels raised and rear or front wheels on the ground as this may cause serious and expensive damage to the transaxle. If it is necessary to tow the vehicle with the front or rear wheels raised, always use a towing dolly under the rear or front wheels.

Q What's a dump valve and what does it do? What are the different types of DV?
The following three related topics are utter steals from another Turbo site - no apologies ... it's common knowledge as long as you subscribe to every potentially related list! "The purpose of a dump valve is to allow the turbo impeller to carry on spinning, when the throttle is lifted. If one was not fitted, the impeller would stall against the pressure that would build up, when the throttle butterfly closed, blocking the passage of intake air. Without a dump valve, the turbo would have to spool up from near standing, after every lift or gear change and the lag would make the car very difficult to drive." "If any dump valve is working properly, it will be fully closed when the car is on boost and there will not be any performance advantage from changing it." "When the throttle is lifted, the vacuum in the inlet manifold pulls opens the dump valve diaphragm and the valve should open quickly and offer the minimum resistance to venting intake pressure. "Vent to atmosphere" dump valves (the noisy ones) offer slightly less resistance than re-circulating ones (as fitted to Scoobies), but will allow air to enter the intake manifold through the valve when driving off boost... giving false air mass sensor readings. This is because the amount of air passing the air mass sensor is not the total amount of air that the engine is breathing in." "In a re-circulating system, the dump valve still allows air in, through it, when off boost. But that air has passed the air mass sensor." "As for sequential dump valves... hmmm. The best dump valves are the ones that go fully open to fully closed as quickly as possible." "Even with vaccuum in the manifold there is positive pressure in the intercooler side of the throttle body. At a brisk cruise off boost you could get up to 0.4 bar pressure. (and you could have up to 0.4 bar of vaccuum, so 0.8 bar differential) If the dump valve opens at approx 0.4 bar the differential will definately keep it open if the spring is too weak. If you want an externally venting dump valve then the Bailey Motorsport EVO one is the way to go. It has a double piston in it. The bottom one stays shut and allows the top one to open under the conditions I've described. The two open together when you come off hard boost so doing their job. It ensures there is no air leakage from the system except under proper dump conditions. Spent nearly 6 months trying different types on my Cav turbo. When this one became available ... worked first time with no probs."

Q My HKS SQV makes a high-pitched "chirping noise" - how can I get rid of it ?
The squeaky noise is normal for a standard SQV. If you want to lose the high pitch noise HKS do a replacement vane for the unit. It makes a huge improvement over the Japanese sound of the original. The replacement vane is widely available for about 12 gbp. The vane allows the valve to dump pressure without any whistle, which sounds great when used with a cone filter (super powerflow etc...).

Q What do I look for when buying a car?
"Things to look for on GTi-Rs when purchasing, I will assume it is a fresh Japanese import to the UK. First check for the basics, smoke out of the exhaust, oil colour, water colour in radiator. If it is smoking don't buy it, if the colours are off see if it will be fully serviced. Check the hoses under the intercooler for cracks, they dry in the heat and will crack after about 3-5 years, makes them very weak. While the intercooler is off check for oil on either side of the endtanks, If there is oil in the intercooler this can cause the car to smoke and is most likely caused by a lack of oil changes or a broken/blocked oil separator. Start car and listen to idle if is rough O2 sensor could be gone, also check the dump pipe on the turbo to see if it is moving/shaking against the turbo, this is caused be some loose nuts and is easy to fix. When driving the car don't test the radio :), listen for clunking/thudding noise when driving straight/around corners these noises will be the wheel bearings, if the car has 16-17inch mags the wheel bearings will not last as long as they should. these are easy to fix if you have the tools otherwise it takes about a day to do all four and will cost about 50 pounds for each one excluding labour. Check boost level, if it goes off the gauge it will have some sort of computer/chip upgrade of boost controller. These computers and chips are ok as long as you can get 98 octane gas which is what they use in Japan. Using a chip/computer/boost controller on low octane gas can cause collapsed pistons, bearing wear, smoke, and dead engine in the long run. See if it will be easy to reprogram the computer or buy a reprogramable one. Check the glove box for holes and the dash for sticky residue, this can indicate the placement of other controllers that would suggest the car has been running a [lot] of boost and like most young guys in Japan the car may have been raced. A roll cage is also a good indication of this :) Again in the car, listen for whines from the drivetrain, if there is any whines from the rear of the car the rear diff is stuffed. If the whine is from the front of the car it can be the gearbox or the front diff. If the whine is all around the car it could be both diffs and gearbox or the centre viscous LSD. any of these will cost a packet to replace. Try over 1000 pounds for any new diff. When in first gear there is most likely to be whine, I haven't worked out if this is from straight cuts gears or if my bearings are [worn-out]. Any other whines in different gears will most likely be the gearbox bearings or diffs. Check all the electric windows if it is the road version these seem to break easy and will be held up by wood in the door. Check the chassis number it should be something like RNN14-xxxxxxx. I can't remember if it is 7xs or 6xs. The rally versions will not be numbered or will have no rear wiper, [cheap] vinyl seats, manual windows, and mirrors. These are very limited but normally sell for the same price as the road version."

Q I've heard that the MAF sensor may give problems - what is the fix?
MAF Sensor grounding First, you'll need a digital voltmeter and a small flat blade screwdriver. The MAF sensor is located just past the air intake. You'll need to pull back the rubber cover to expose three wires. On mine, the outer two were orange, the middle one is white. The middle pin is where we need to get a voltage reading from (with the engine idling). Take the positive lead of the voltmeter and make contact with the middle wire. The negative lead should be pressed to one of the ground connectors on the engine block, near the firewall, right behind the fuel injectors. You might have to look hard to see them, just look for a bolt with several black wires running to it. Took me a while to spot it myself, several vacuum hoses in the way... The voltage read should be less than 9mv (.009v), if it is above this value, the sensor needs to be regrounded. To do this, a wire needs to be run from the middle pin to the ground lug. You'll need to remove the connector from the MAF to get a good angle on it. On either side of the connector is a small opening for a small flat blade screwdriver. There is a wire that runs around the connector to hold it in place, you need to pry this wire outwards, then move the connector back a bit. Do one side, then the other, and it should pop right off. I'd never seen this type of fastener before, once you have it off you'll see what I mean. You'll want to solder a new wire to the middle pin, make sure you get a good connection. Then, run the other end to the ground lug. If you want to do the job right, you'll want to get a connector from Radio Shack or other electronics store that has a ring that you can crimp the wire to. I don't remember the size of the bolt, so I'm no help there. I just looped my wire around the bolt twice and put it back on. I may go back and fix it up nice some other time. Once the sensor is regrounded, the voltage should drop significantly. Mine was at around 11mv, after the fix it went down to less than 2mv.

Q What's this pinking/detonation stuff and have I got it?
Pinking is where the ignition is too far advanced..the burning in the combustion chamber happens too early and actually tries to push the piston back down before it's reached the top. Detonation is where the temperatures inside the combustion chamber are so high that the fuel/air pre-ignites before receiving a spark. Same effect as pinking i.e. burning occurs too soon. 98RON "resists" detonation better than 95RON. This is why cars running high boost need methods of lowering the temp inside the chambers - Water Injection is one method. Nitrous injection also has very good cooling properties. And I believe the grade of spark plug is important..one that runs too hot will likely pre-ignite the mixture ?

Q:What spark plugs should i use in my GTiR ?
The standard plugs ar NGK 'R' series. Model no PFR7B. Cost about 50GBP per set.If you go to Nissan (in the UK anyway) they will try to sell you PFR6B plugs. DO NOT BUY THESE. They are 1 heat range hotter (70-100 deg C) and can result in detonation when running on standard unleaded (95 RON), though you should be on super unleaded anyway. Certainly you'll run in to problems if you increase the power, whist running these plugs.Why Nissan do this is unclear, however. The plug gap according to Nissan is 0.9mm, though NGK , from where the plugs are sourced, recommend 0.8mm. My car runs slightly less than 0.8mm with no problems. As you increase power by between 0 and 50bhp, you should think about gapping the plugs smaller, or run the risk of the spark blowing out at high engine rpm. Running more than 70bhp over standard, and you should consider moving 1 heat range colder on the plugs, to a PFR8B.

Q: I cant find a replacement battery in the UK !
The GTiR battery does not conform to any known standard - the poles are too small , and the depth (front to rear) of the battery is very shallow.No other battery will fit due to the constraints of the battery tray (though easy to overcome), and the standard battery clamps cannot be forced to fit a 'large pole' battery.Approx dimensions are 200x200x130mm. I found this battery at only one location, on the shelf at Bristol Batteries in Bristol, UK. The battery is an ATLAS MF054, and cost 40GBP.

Q: My clutch pedal creaks / squeaks. How do i solve it ?
You dont. No amount of WD-40 will solve it, as its more than likely you have a common GTiR fault. The clutch pedal eventually comes away from the bulkhead, after many years, or a hard life. The pedal probably has excess movement from side to sode as well. The most common way to fix this is to manufacture a bracket from 6mm steel, around 3 inches long, with a 90deg twist in it. This is then bolted to the top of the clutch pedal box, and the steering column. You have to remove most of the dashboard to facilitate this, however.If you let the squeak get worse, eventually the pedal box will fail, and the clutch pedal will bury itself in the floor.

Q: How do i change the oil filter easily ?
Its right at the back of the engine on the drivers side, and looks like a pig to change. But its not that bad. Simply remove the drivers side roadwheel, and where the track rod passes back into the engine compartment from the wheel, there is an enlarged opening to remove the filter quite easily. It can be seen just inside the hole.

Q: WHAT ? My GTiR has a dump valve as standard !! Where ?
OK. Stand at the front of the car. Look under the right hand side of the intercooler, at the back. Looking down, you should be able to spot a metal pipe, about 30mm in diameter, with a welded 45deg bend in it, going downwards deeper into the engine bay. This is the dump valve outlet, returning to the inlet to the turbo - yes, its a re-circulating dump valve. If you then run your hand underneath the throttle body, about 50mm from the intercooler connection, you'll find a 33mm outlet pipe going straight downwards from the throttle body. This is the inlet to the dump valve. It is actually situated right underneath the intercooler on the rear right hand side. It can clearly be seen if the intercooler is removed.

Q: How do i remove the intercooler ?
OK, remove the four easy 10mm bolts from the alloy heat / water sheild. Now remove the set-back 10mm bolt on the rear left hand side of the sheild, and remove it. Undo all four 12mm intercooler mounting bolts (easy to spot). Slacken the jubilee clips securing the rubber pipe to the turbo outlet, and the rubber pipe to throttle body. Leave the pipes connected to the intercooler, though. Unclip the throttle cable from the left side of the intercooler. Move over to the right side of the intercooler. Underneath, you should see a pipe with a 180 deg U shaped bend in it , clipped to the bottom of the intercooler.This is the gearbox breather, and can be removed. Disconnect the small diameter pipe from the metal pipe on the same side, underneath, then remove the small diameter pipe on the back of the intercooler between the throttle body and the intercooler, on the top. Remove the intercooler. You MUST reconnect these small pipes upon refitting,as they control boost.
 
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