Tricky-Ricky

If anyone is still having trouble with their clutch bite point/feel, you might want to try this. This is a little mod I did on my Skyline 350GT, which is essentially the same as the Z apart from the body, it helped with clutch control and feel immensely, it may help if you're mechanically inclined. Disclaimer: if you decide to go ahead with this, ITS AT YOUR OWN RISK! if you don't feel competent then don't bother. I have felt for a long time that my clutch is rather heavy and too quick, as in short engagement window, and lack of feel, which spoils the driving experience, now I have already removed the clutch pedal assist spring, which did nothing but make it even heavier. So with this in mind i went hunting on the US forums and came across a thread that a guy with some engineering experience came up with an idea of how to combat this, but basically altering the leverage/fulcrum point of the pedal, his opinion was as mine is, that the master/slave cylinder combo was mismatched, and didn't work well. Anyway, his idea was to fabricate a rather over-elaborate method of shifting the fulcrum point further up, and so reducing the effort needed along with increasing the engagement window, which makes clutch control a lot easier. Now at first I thought I would be lazy and see if I could order one of his kits, but he only makes them for LHD cars, so I decided to bite the bullet and pull out my entire clutch pedal and see if I could make a much simpler modification and achieve the same result, and the answer was yes I could with nowhere near the effort that he had gone to. So its just a case of removing the pedal and disassembling, then marking and drilling a hole of the same diameter about 15-20mm higher up from the original clevis pin pivot hole, I actually just used the clevis and held the bottom edge of it flush with the old hole and using the original to make a mark, I then drilled this to the correct dia, so I could refit the plastic/nylon liner back in, thats it for that bit, you could probably put it all back together and live with the slight master cylinder rod misalignment, as it allows for a small amount. However I decided that I dint want to live with it, and so I just fabricated a small metal plate drilled with two clearance holes to fit the same size as the master cylinder rod, the holes in my case where drilled again at about 15mm centers, so I have enough clearance for the two adjusting nuts, the pics will explain it better, but you get the gist I hope. Just to avoid confusion, the lower bolt/nut are where the original master cylinder rod with the two lock nuts would go when it's fitted, the bolt was just there to check alignment etc. And the result! well i wouldn't go so far as to say that it halves the pedal effort, but I would say it now requires about 35% less effort to depress the pedal, and the other result is to give a much wider engagement/disengagement window, which results in about 60% more feel, so well worth the trouble IMO. Obviously, you will need a little mechanical know-how for this, but it's not rocket science, but I guess you will have to make up your own mind as to whether you feel confident enough to tackle this.

I think there is a lot of confusion here on engine loading while moving, actually turning the wheels, and just during idle, Of course there is going to be more stress on the engine during driving the wheels, and its very varied, However we where discussing warm up and leaving the engine idling in particular, driving the car is adding dynamic stress to the engine which it was after all designed for, and if driven when cold with common sense, its not going to be a problem, after all thats what the gear box is for. The general consensus is that as far as engine wear is concerned, the first few seconds when started from cold, and hot to a slightly smaller degree is when the most engine wear takes place, due to zero to low oil pressure, the next is during idle on the valve train as said, the next factor is oil, but that's a whole separate subject. Adding a little disclaimer here for the pedants, there are other danger areas of engine wear that are also not related to this thread, which has I think run its course, as there are always going to be differing opinions as to which practice is the best option, either way I doubt anyone is going to see a big difference as most of the time we don't keep our cars long enough.

Have you still got the evap control solenoid fitted? check that's working and there are no leaks.

I'm sure you posted a while back that driving in a high gear taxes the valve train more. I would like to know a little more as you seem to know your stuff Never would have said that fella, stress on valve train reduces as the RPM rises, its the old reciprocal mass thing, the slower it moves the more force is required to move it, and as the valve train is moving at half the engine RPM...... Its not that an engine left to idle on a regular basis is going to fail, its just going to show considerable more valve train wear than an engine that's not, and likely need to have valve clearance's adjusted/shimmed more frequently, and the cam belt/chain will also require more frequent replacement.

Warm up is all about oil and stress, the most stress on any four stroke engine is on the valve train at idle, so leaving an engine to warm up is only going to cause accelerated wear to these component's, that why nearly all manufactures recommend starting and driving the car, obviously common sense is required on how its driven, Engines back in the 50 to the 80s where recommended to warm up before being driven, but that has a lot to do with oils, todays oils are far superior, and also engine design and material's are far better, so expansion rates of metals within the engine are pre calculated and clearances are adjusted to suite, its also about emissions now, so that's also a consideration,.

After this comment I thought I had better warn you as to the possible cause and urge you to investigate, its not just a heavily worn and noisy engine that can show low oil pressure either, but its up to you what you do about it.

That pic looks like its about 15psi which is slightly low my DE would show around 20psi at idle, but obviously 30psi at any serious RPM is way too low you should be seeing around 60psi by 2-3K RPM, check the sensor output against the manual data. You should never ignore an oil pressure gauge reading if low, biggest mistake going what would you rather pay for a new gauge/sender or an engine rebuild? How is an oil temp gauge more important than a pressure gauge? especially on an N/A engine, its never likely to get very high unless you forget to put oil in it, The first thing I do on any car that doesn't have an OPG is to fit one.

The should be OK if you have a JDM Z, but not UK.

Definitely fit an oil temp gauge, an oil pressure gauge is also a very good idea, As far as thermostatic oil coolers, , even when the thermostat is closed there is always a small flow of oil through the cooler, it helps with not suddenly introducing cold thick oil into the oil system, so In effect if the oil is already cooler than it should be, that minimal flow wont help. Because the std system has a water cooled oil cooler (unless you have removed it?) having a larger rad also has a direct influence on cooling the oil, so this will also just compound the issue.

Neither are really needed for normal driving, and that's why your seeing low temps, the oil cooler in particular is not at all necessary unless your running a track car, and the big rad is just compounding the issue, I would presume you have a thermostatic oil cooler take off plate? other than removing them the best you can do for now is to cover the oil cooler to stop airflow through it, and partially cover some of the rad, unless you oil temps are getting to 100c you will never get rid of the water vapor and acidic contaminants produced during the combustion process, its not good for the engine.

I to would be interested to know peoples experience of this as in theory the UK should be a fair bit better as AFAIK the UK ECU uses wide-band lambda feedback, so fueling control should be far better.

Did you check that the caliper pistons are moving freely and not stuck? other than that I would also try bleeding the system as if there was air present in the side the air would heat up and hold the pads in contact with the disc and cause overheat issues, which could cause lock up.

Thank you! IMO its not much harder to actually remove the pedal than adjusting the bite point, the hard part is getting in there and positioning a light to see by, it probably easier to remove the seat first LOL!

This is a little mod I did on my Skyline 350GT, which is essentially the same as the Z apart from the body, it helped with clutch control and feel immensely, it may help if your mechanically inclined. Disclaimer: if you decide to go ahead with this, ITS AT YOUR OWN RISK! if you don't feel competent then don't bother. I have felt for a long time that my clutch is rather heavy and too quick, as in short engagement window, and lack of feel, which spoils the driving experience, now i have already removed the clutch pedal assist spring, which did nothing but make it even heavier. So with this in mind i went hunting on the US forums and came across a thread that a guy with some engineering experience came up with an idea of how to combat this, but basically altering the leverage/fulcrum point of the pedal, his opinion was as mine is, that the master/slave cylinder combo was mismatched, and didn't work well. Anyway his idea was to fabricate a rather over elaborate method of shifting the fulcrum point further up, and so reducing the effort needed along with increasing the engagement window, which make clutch control a lot easier. Now at first i thought i would be lazy and see if i could order one of his kits, but he only makes them for LHD cars, so i decided to bite the bullet and pull out my entire clutch pedal and see if i could make a much simpler modification and achieve the same result, and the answer was yes i could with nowhere near the effort that he had gone to. So its just a case of removing the pedal and disassembling, then marking and drilling a hole of the same diameter about 15-20mm higher up from the original clevis pin pivot hole, i actually just used the clevis and held the bottom edge of it flush with the old hole and using the original to make a mark, i then drilled this to the correct dia, so i could refit the plastic/nylon liner back in, thats it for that bit, you could probably put it all back together and live with the slight master cylinder rod misalignment, as it allows for a small amount. However i decided that i dint want to live with it, and so i just fabricated a small metal plate drilled with two clearance holes to fit the same size as the master cylinder rod, the holes in my case where drilled again at about 15mm centers, so i have enough clearance for the two adjusting nuts, the pics will explain it better,but you get the gist i hope. Just to avoid confusion, the lower bolt/nut are where the original master cylinder rod with the two lock nuts would go when its fitted, the bolt was just there to check alignment etc. And the result! well i wouldn't go so far as to say that it halves the pedal effort, but i would say it now requires about 35% less effort to depress the pedal, and the other result is to give a much wider engagement/disengagement window, which results in about 60% more feel, so well worth the trouble IMO. Obviously you will need a little mechanical know how for this, but its not rocket science, but i guess you will have to make up your own mind as to whether you fell confident enough to tackle this.

Sounds a bit sad to me, next there will be a thread about running a hose from the air-con unit in the cabin to get more cold air to the intake and increase BHP seriously I have see the question asked on another forum.

You cannot be serious!

Spacers will effect geo, think about it, by fitting spacers your extending the effective length of the suspension arms, this will accentuate any miss alignment present, and it doesn't take much to notice, it will also increase unsprung weight because of the wheel being pushed further out... like adding heavier wheels.

I have always wondered at the point of fitting light weight crankshaft pulleys to any car really, sure they can look good (if you can actually see them) but for the sake of such a small BHP gain that you wouldn't notice anyway...... and the risk of premature failure of major engine parts is more than enough to put me off.

I'm sorry what am I looking for? where is it damped? If you look carefully at the junction of the two diameter pulleys its decoupled by a thin rubber insert.

Here is a pattern VQ35DE crankshaft pulley, if you look you can see where its decoupled/damped, http://reindeerparts.de/en/autoteile/NDS-VQ23-CRANKSHAFT-PULLEY-ENGINE-VQ23DE-VQ35DE-OEM-to-compare-12303-8J101Model-NISSAN-MURANO-Z50-2002-2007.html The DE engine dose not use any balancer shafts, the later VHR may but I don't think so.

ATI do an expensive harmonic damped aftermarket crank pulley, so do Boost logic, all the pattern part pulleys are harmonic damped based on the std part, don't quite see the point of running an undersized pulley, why over speed the alternator, power steering pump and air con pump.

It may not look like it at first glance, but I think it will be, I really cant think of any modern engines (1990 on) that dont have a harmonic balancer.

A lot of engines are designed to have external vibration damping, the reason for this is because during the firing of each individual cylinder torque stress is imparted into the crankshaft which makes it deflect setting up vibrations, At certain RPM this vibration can set up a resonance which amplifies the stress to a point beyond what the crankshaft can stand, which in extreme cases can cause crankshaft failure. If it has a harmonic crank pulley as std then if you fit a solid undamped item you run the risk of this happening, maybe not in a few thousand miles but its eventually likely to fail, especially if the engine is tuned or used hard, you pay your money you take your chance.

Not really, worst case scenario is that plugs are not removed for considerable millage and the oil or grease hardens and makes plug difficult to remove, what usually happens though is that plugs are fitted and left, and due to combustion pressures carbon is built up in the actual first few threads and makes removal difficult and can sometimes cause the alloy part of the thread in the head to strip. Personally I would rather have some grease or oil acting as a block to carbon formation.

I use a drop of engine oil or copper grease if the plug has proved a bit difficult to remove.