djr81

Seeing as some of you want numbers, here are numbers: Take the case of (for example) an R32 GTR. Weighs 1600kg with drivers & fuel. It travels at 72km/h. Why 72km/h? Because it gives you nice simple numbers to work with when converted into other units. Things to know: Kinetic Energy (Linear) = ½ * mass * velocity squared. This is how we represent the energy of the car travelling in a straight line. Like all energy it is measured in Joules. Rotational kinetic energy (ie flywheel) = ½ * rotational inertia * angular velocity Rotational inertia is for the flywheel, obviously. For a cylinder (which is what the flywheel can be represented as, albeit a very short one) I = ½ * mass * radius squared. Angular velocity is engine speed, measured in radians per second (Not rpm) SO: Kinetic energy = ½ * mass * velocity squared =1/2 * 1600 8 20^2 =320,000 Joules. Rotational inertia of the flywheel calculation. Mass = 10kg. Radius = 0.2metres (Approx) I = ½ * 10 * 0.2^2 = 0.2kgm^2 Rotational velocity of flywheel. GTR does 28.5 km/h per 1000rpm in fourth. ie 72 km/h = 2500rpm. 2500rpm = 265 radians per second. Rotational kinetic energy calculation E ® = ½ * rotational inertia * angular velocity =1/2 * 0.2 * 265^2 =7000 Joules. So the amount of kinetic energy in the rotating flywheel = 7000 Joules The amount of kinetic energy in the car = 320,000 Joules. Or to put it another way 2%. So a 3kg lighter flywheel will be less again, about 1.4%. If you think you can feel or even measure a 0.6% difference you are dreaming. It is the equivalent of 10kg of dead weight. So what does this all mean? The major difference in the flywheel masses are the following: 1. With a heavier flywheel there is more rotational inertia in the engine which is felt when the clutch is in. This extra inertia feels better when you pull away (slowly) from the lights. It also acts as a mass damper to make the engine idle smoother. In other words it makes Nanna happy. 2. A lighter flywheel stores less energy than a heavier one. If you have a track car energy stored in the flywheel is energy not used to make the car go quicker. So you run the lightest flywheel you can. 3. The importance (or otherwise) of flywheel mass is larger in lower gears as the engine is rotating faster relative to the cars speed. When the car is in gear you cannot tell how heavy the flywheel is.

Not sure that it is. Super sprints have been around for years. It has become more popular over the many years & the grids of cars have been getting quicker and with higher quality cars in them. Then the "time attack" thing comes along & the hype mongers pronounce the whole idea was invented in Japan a couple of years ago. Then a bunch of fitted cap types get on board because A: Drift is dying & B: Hype. Which is pretty much what is wrong with "time attack". Dont misunderstand me I love the cars many of which are head and shoulders infront of most of what is allowed to go racing. Full credit to those who are having a go. As an aside there are state based super sprint championships & a yearly national Australian championship. Done under CAMS. I find the race types who want to be seen as really hard profess to hate CAMS & V8 Supercars. Less so time attack.

Calm down dude. You will burst a blood vessel or something. Hug? Actually I wondered wtf Nissan are thinking when I was looking at a busted Lanchester balancer in the sump of a 4 cylinder diesel in a Navara.

Yeah maybe. Dont mount the shock on the bottom eyelet & see if you can move the shaft around where it goes through the top plate. Just understand that a fair bit of force is present when you drive around on the road & FFS dont do this with a car on a jack.

Yes but that isnt going to tell you anything about the state of the top bearing. If that is the noise it happens when the wheels goes down into a pothole or an undulation. The top mount of the damper shaft then gets unloaded and when the load comes back on (ie the wheel gets to the bottom of the pothole) the top bearing goes clunk.

You are missing my point. Even when the spring is fully compressed the gas pressure within the shock absorber will force the suspension onto full droop. It takes a bit of force to compress the shock absorber on its own.

Falcon can handle 2300kg. NFI about the commodore.

Lycra clad promo chicks>all that stuff.

Just keep in mind that removing the spring tension wont remove all tension from the shock as there is the internal gas pressure forcing the thing apart. So make sure you have some decent pry bars to get the things out.

All a flywheel does is store energy. So yes a heavy flywheel stores more energy as the motor moves up through its rev range than a light one. But when you put your foot on the brake that energy is converted to heat. So clearly in a track car (part one of the original question) there is really no downside of having a lightened flywheel. A flywheel doesn't balance movements. It dampens them. A straight six (like in oh, say a skyline) has a balanced motor whereas a POS Emo has a four which has a second order harmonic that only a pair of Lanchester balancers can ever remove. So yes your bucket of bolts four cylinder diesel may well benefit from a heavy flywheel. But really, so what?

Time attack is a super sprint with boundless hype. It is almost all about the hype. You know, like drifting was a few years back before it died in the arse. It is the fastest growing motorsport because any number of people who dont have a pharken clue decided it is. So some lean-to in a back alley in a rural slum in Japan gets written up as the greatest, all inspiring leader in time attack trends. Or some fourth rate (if it is that good) track in a desert in America with all you can eat tumbleweed is now the centre of the time attack universe. It must be true I read it in a magazine & saw it on a DVD.

In a way that is sort of the point. No one really cares if there is not a race in any one country as long as there is a race somewhere. Korea or Bahrain or Malaysia or Abu Dhabi or China or the sphincter of the universe or pick any country with no motorsport heritage. Nobody cares if they miss a GP. Well ok maybe there are a few sponsors who do. Maybe. On the other hand losing Monaco or Spa or Silverstone does upset people. The upshot of this is Bernie can just go on extorting money from the current list of despots until they have nothing left. Then move on. The hard bit comes when you have to drop somewhere like France or Canada or Australia because they can no longer affort the stupid sanctioning fees. Nice work on the auto correct. I am guessing that was you Baron?

Mine did a not dissimilar thing - easiest check is the rear sway bar bushes & more particularly the drop links. If there is slop in them chances are that is your problem.

Can I ask where you got the radiator from?

The proper way to do it is the same as the Gibson Motorsport GTR's. They ran a radiator with a reduced height which allowed plenty of room for an airbox fed from the grill. If you haven't got a radiator yet I would suggest this is the best way of going about it. Failing that take some air feed from the ducting on the passenger side under the headlight.

Well to be fair that was all he asked about. I chucked a lightened flywheel in my car & it is still driveable on the street. To put it in perspective a cam change had more of an influence on how it responded off idle than the flywheel weight change.

People who say that a lightened flywheel reduces the amount of torque the car produces are speaking through their collective arses and should be ignored. For track work run the lightest flywheel you can find. If you can save 3kg on rotating mass then do it. For drag work run a light flywheel but you have to be able to launch the car & the lighter the flywheel the more sensitive it is to getting the launch rpms spot on. Also you are more likely to have clutch issues so what you have been told makes good sense. For drifting just cable tie the old busted one together like all the other drift crap. Then talk it up with the aid of incomprehensible hand gestures & a stupid fitted cap worn at an angle.

I will probably end up buying a new crank - just the stock Nissan one. Other than the head gasket I am not fussed. May just let the engine builder sort what they need. It is easy enough to drive the car to Perth & get the train home to Bunno. Then do the reverse when it is finished. I have a couple mobs in mind for the build but I want to get my ducks in a row before I annoy anyone too much. The "custom secret specification" types wont be getting a look in.

Yeah they are Mahle. Rods are the basic H patterns - ie not with the flash bolts. Good enough for what I want. Got some ARP studs as well. Need the head gasket, other general gaskets, bearings and to decide about the crank, ie new or refurbished existing. The bolt on stuff is all covered. Visa card needs to recover a bit too. Hard bit is finding someone over here in WA to build it, ie knowledgeable, interested, trustworthy & who will actually listen to what I want. Unfortunately we have tuner wars whereby whoever you are talking to will promise you their tuner/engine builder is brilliant and going anywhere else will ensure the engine blows in very short order.

I have a soft spot for Bargs vs Murphy at PI in the early/mid 2000's.

I was just going by the graphs. So there is a fair chance I have it wrong. It depends on how you extrapolate the Z32 curve or even if it runs above the 4.25V shown. It may be worth checking my PFC to see what the maximum AFM output voltage was to get an idea of how it relates to RWHP. Nismoid: out of interest how many horsepowers do you reckon a Z32 is good for? Stabby: I see what you mean - either 2*300=511 or the 300 or the 500 is wrong????

I am a bit the same. Cant watch it live any more. Too much filler no killer. The over blown hour plus long intros & all the shite they broadcast is hopeless. Glad they canned the shootouts too. Cromley is good value. Has been for years. If you bought Chevrons volume four (?) of the old ATCC DVD's you would have got to hear him at Oran Park circa 1983. Gold that is, as is Moffat's fan friendly demeanour.

Wasnt Longhurst vs Morris quality. "There was a bit of push and shove," Holdsworth said "I went up and asked for an apology because he took me out, but he wouldn't give me one. I told him what I thought of him and he pushed me and it got a bit ugly. Which I guess means it looked like two girls going at it with handbags.

Cheers. I think I will end up with a MLS of some description. Maybe ACL or Tomei. Here are some other bits I prepared earlier which should fix a couple of weaknesses.

Yeah, thanks Baron