djr81

A few things. The quoted cost of the GTR's was affected by two things: 1. Freddo Gibson talking it up. 2. Electronics being massively expensive in the early 90's. The figure of $750k was never credible then, nor is it now. The taxis are currently being reengineered to try & get their cost down to under $300k - this is the Car of the future they keep banging on about. They look like they will fail in this endeavour which is a worry because the reduced costs are one of the most important reasons for doing all the work. RB26s did not require rebuilds for every race. Thing about it - with the boost & rev limits in place just about anyone could build a motor to survive those conditions. Nowadays with control cams, minimum component weights, maximum engine speeds, sequential gearboxes, much better ECU's etc etc the motors last longer. They dont perform anywhere near as well as the could, but they last longer.

You mean the old oval shape with the three chicanes? I cant remember what year they had a massice start line shunt - there were only a handfull of cars left & Tyrrell (?) ended up with a bunch of points. Other than that the cars used to disappear into the pine forest before the inevitable happened & they blew their engines to a million pieces.

Yeah I used to watch it and think "Other than not turning up I wonder if Alan Jones could try any less?" Then sure as sht the next GP Eastlake would do the intro: "Alan cant be with us tonight." Gold.

Tomei make a little bit of electronics - you can plug it into the computer & it stops the hicas system from showing an error.

Yeah you wont go far wrong with Cusco. They are better than the Whiteline ones because they are both stiffer & lighter. THe only reason I run a front Whiteline sway bar is as near as I can tell it is a little softer than the Cusco. But there is not much in it. Hey, they may suit you just fine.

All the torque split controller does is reduce the influence of lateral grip on the way the system works. Nissan programmed the system to reduce front torque when the car is cornering (relative to driving in a straight line) so it behaves more like a RWD & is perceived to be more fun on the road. There are gains to be made by changing this. Or in other words gains to be made by making the GTR behave less like a GTST. Due to them not running a differential (Ie they have a locked rear axle with a pinion, spool & nothing else) the V8's dont turn in at all well. Which is why the drivers have to carry so much brake into turns. So compaired to a V8 a GTR will turn in brilliantly. The amount of commonality between a Gibson GTR & a stocker is massively more than a V8 supercar & a VT. Group A cars had what the production cars had. That was, after all, the whole point. Actually the GTR had a heap of ballast as well. Does a completely different set of rules & many years of tyre development explain it away. Absolutely. The ATTESSA system is not the greatest in the world. It is, however, sufficiently useful to be more than worth the weight. Which is the point, after all.

But why would you. I mean other than so you could boast you had done the stupidest conversion in history?

I used to love the Alan Jones pre race commentary. He would be reading the grid out & stumble over the names of all the back markers because, after all, who really gave a fk about the name of the ninth different pay driver in the Minardi for the year? Good work, good prep. Big Darryl Eastlake on the other hand was always a complete fkwit. Oh gees you can see the emotion written all over his helmet etc etc..

That would have been Wheels magazine. If you are really keen I can dig it out as I have them all stuffed in a cupboard at home. The Mp4/4 was probably one of the greatest/most dominant cars of all time. Just a shame the Brabham BMW it owed so much to was a total dog.

Yeah 1998 is where it is at. From memory Schumi tried to punch on with Coulthard after the Liberace? Dont hating on Damon, he was alright & the Jordon promo girlies were better than anything Force India has ever used. Help me out Baron, what year was it that Hakkinen did the epic over take move on Schumi - it was at Spa & must have been 1999 or there abouts?

Yes. Otherwise your car will be stiff in bump settings but relatively soft in roll. Which is not a very nice combination because it wont absorb road undulations very well nor probably corner as well as it could. Exactly. Although I would term it more so as less understeer. Not necessarilly as spring rates can be a bit of a personal preference thing. But I would say that they are pretty stiff in the overall scheme of things. For what it is worth mine are about half what the Apexi rates are. It does depend on alot of other things, however.

The problem you will have is that the spring rates from Apexi are so high that neither the Cusco nor the Whiteline offerings will be anything close to matching the stiffness of the springs. Rolls tiffness is a combination of spring rate & anti roll bar rate after all. Also the balance can be changed by camber settigns, spring rates, roll centres (read ride heights). So there is no one right option. For what it is worth I use a Cusco rear and a Whiteline front.

No. You are so profoundly wrong it makes baby Jesus cry.

A couple of points: The graph is clearly not that for a tyre used on a GTR. It is simply there to illustrate the point about the relationship between friction coefficient and load. Secondly and more importanly, there are a number of other effects your calculation does not include which are fundamental to the way a car is set up. In no particular order: Camber settings. The relationship between camber angle and the lateral grip of a tyre is well known. So in our case it is easy to use more camber on the front end that the rear (Which is typical in anycase as camber hurts traction) to help balance the car. Spring rates. As I mentioned in an earlier post what spring rates you use has a strong effect on the load transference front to rear when the car is cornering. In this instance a softer front spring will allow the front to grip better. Anti roll bars. These have the same effect as springs in roll. A harder rear bar will load the rear tyre more & promote oversteer. Roll centres. The difference between the centre of gravity and the roll centre (which are different front and rrear) defines the roll couple. This in conjunction with the roll stiffness of the car is also used to preferentially load one end of the car up. Between all these tiems there are enough tools in the tool box to compensate for the poor weight distribution. Added to which in any half developed track car weight reduction and relocation are two items that are very high on the agenda.

Well it is your assertion that the GTR understeers. I have spent alot of time & money to get my car balanced. Yes it still does have an amount of understeer mid corner but, depending on what gear etc you are in, even with the torque all the way forward it will power on oversteer. Compared to a WRX or an Emo it is positively tail happy. At the end of the day you set it up to do what the lap timer says is quicker and drive it accordingly.

Yes you would install a torque split controller (On a 32 in my experience). You then set it up to transfer as much torque forward as possible (based on the assumption it is of the type that interferes with the lateral accelerometer input to the ATTESSA system). The GTR's were set up to drive nicely on the road. How you set the up for the track is a whole different story.

You enter how many wheels you want to buy, ie 4. NFI what the difference between an A & an O disk is, however. The price is per wheel.

Soem tips: Ask them to check availability before you send them any money. You cant decide what size/offset to use or you cant get the website to reflect what you want?

Yes I had much the same happen. Transient/part time vibration from the drive train. It was a stuffed front diff. Anyway with a bit of fiddling the front diff can be replaced without too much gear having to be removed. Added bonus is they are cheap too as alot of people want RB26's and have no use for the diff. Just make sure you get it shimmed properly.

Cars today (yes, even GTR’s) are not limited in their braking capacity due to their weight. They are grip limited. The difference between a lighter car under brakes & a heavier one is minimal. In any case it is the least important aspect (time wise) of a corner. Your assumptions are wrong about a GTST cornering better anyway. Why? Because of the following. To get anything line acceptable traction with a decent motor a GTST has to run a soft rear spring. To maintain reasonable roll stiffness you then need a stiff front spring and have to make the anti roll bars match. What does this mean? It means the suspension set up makes the car understeer. A GTR does not have to run a soft rear spring for traction – hence can dial out the understeer with a better suspension tune. End result is the GTR is going to corner better. Once your GTST has struggled its way through the corner it gets to the point of getting the power down. Already hamstrung by a lack of traction you get a double whammy. All that magic aero you are carrying serves to massively increase the aero drag on the car. To the extent that is will accelerate slower than the GTR. Touring car spoilers have horrible lift on drag (L/D) ratios. So the several hundred kgs of downforce you need will come at the cost of a large amount of drag. How much – at any reasonable speed more than the weight of the 4WD system in the GTR. Actually no, lets not. For someone who reckons it is “all about the tyres, bro” I would have thought, at the very least, you would have bothered to take the time to understand one of the fundamental properties of a tyre. This you can take to the bank: A tyre’s coefficient of friction decreases with increasing vertical load. At the bottom of the post there is a graph to illustrate it. Note that at 500lb load the friction coefficient is about 1.4. Increase the load to 1000lb and it has fallen away to 1.25 of there abouts. It has, in other words, decreased. As in it is not constant or even linear. The graph comes from Carroll Smiths Tune to Win. I would suggest you read it or any of the other books out there on car suspension – they all make the same point – tyre behaviour is non Newtonian. Why is this important? A couple of reasons: 1. It shows that there is not a constant relationship between tyre load and lateral grip. 2. It means you can adjust the balance of a car (ie understeer/oversteer) with sway bars & different rate springs. Perhaps the second of these is not so important for a GTST that has been sprinkled with pixie dust & is therefore the greatest handling, physics defying, most brilliant car ever built. But for the rest of us mortals it is actually useful. You want an example? Nissan once campaigned a thing called a GTSR in group A. It had a front engined RB and rear wheel drive. They replaced it with the GTR. For the highly technical reason that the GTR was faster, everywhere.

Actually there arent alot of variables. It is pretty simple. You have two factors. 1. How many horsepowers your car can produce at a given speed. 2. How much drag you car generates at a given speed. When these are equal you are going as fast as you can. The gearing dictates where abouts on the powah curve the engine is running - hence it influences the top speed. Excessively tall gearing means you dont make all the hp you can and you are therefore slower than may otherwise be possible. Too short on the gearing & you have introduced a new, mechanical limit to things. To go twice as fast you need eight times as much power. Yes, boys and girls, eight times. It is a cubic relationship.

1 kg/mm = 54lbs/inch. So an 800lb/in spring is near on 15kg/mm. Which is an absurdly high spring rate.

My mechanic tends to diagnose faults in my car by A: drinking alot of piss & then B: telling me to go buy something better. Also Placebo is a really shit band. What everyone is actually talking about is confirmation bias. You expect your million dollar oil to make then engine feel better & lo and behold your head confirms it.

Aero is not magic. Broadly (very broadly) if you can generate, say, 20% of the weight of the car in downforcee you will increase the lateral grip by the same amount (you wont really but for the sake of the argument). A GTR with driver is about 1600kg. So you need 320kg of downforce, biased about 60/40 bias to the front. Near enough to 200kg of front downforce. Have you seen what sort of wings are required for this at the usual 100km/h cornering speeds you get in local circuits? Is doesnt happen. The coefficient of grip (friction) will NOT stay constant. It is not constant. It falls away as the loads increase. Well go your hardest. But you will find, as countless others have before you, that you theory is wrong. It is not F1 in the 60's after all.

A 21% difference in lateral grip (Which is absolutely massive) will only produce a 10% difference in cornering speed. There is no way two notionally similar cars ie a GTS-T versus A GT-R will produce anything like that difference in cornering speed. They will, on the other hand, easilly produce a 10% differential in straight line speed based on the GTRs better traction. Given the straights are longer than the corners - well you figure it out. The more wieght = less relative grip. If you double the weight of a car you need twice as much grip to corner at the same speed. Unfortunately tyres will not produce twice as much grip with twice as much weight. I have. Most of it is tripe. The R32 & R34 GTR AWD systems are fundamentally the same. They are both sufficiently advanced to more than make up for their weight. Even primitive, 1980's LSD's work, believe it or not.