djr81

Back in the eighties Renault were the first to use pneumatic valves on their 1.5 litre six cylinder turbo motors. They revved quite a bit more than 12,000rpm. Some bloke called Senna used to drive something called a Lotus with them installed. The reason they didn't rev them harder was that by that period F1 had started in on its stupid fuel capacity restriction era. Caused some of the lamest results you could imagine, ie people running out of fuel in the last few laps of the race & not being able to do anything about it. Why do people want to lower revs and change the engine formula. What is wrong with having a motor screaming its tits off at 20,000rpm? Personally I don't think TDI is the future of anything, not even road cars. Road trains & merchant ships, maybe.

I fkn hate pikies. and/or Caravans? What the &^%$ do I know about caravans?

Well that was pretty much plan A - has worked a treat so far. The fact that the seat is too small & kills me by bruising the living @$%# out of my ribs & giving me back ache from no lumbar support is neither here nor there. The problem is, like you say, that a standard or even reclineable seat with a 4 point harness sucks big time. On the other hand a fixed back with good hip bolsters & the holes to fit the harness doesn't work at all well with the standard belts. Which pretty much leaves me up a well known creek.

To be honest the calculator is actually pretty good. But at the end of the day it is only as good as the accuracy of the FOB price you put into it. Unlike alot of calculators the Imports101 one lists all of the stuff you will end up spending money on. It doesn't neglect stuff & assume you live in Queensland (Which is the cheapest state to get an import into)

Hmm, I am more than a little curious to see how they stack up price wise with the Bridgestone RE55's?

Try the Imports101 website. It has a good cost calculator that actually includes all the necessary items for your state. (Whatever that is). You may be surprised by how much difference to the end result the change in the value of the yen makes when it goes from, say 96 to 97 to the dollar. It works out to be quite a bit more than $50....

It isn't a good plan. You only have a certain amount of time in any case. Why not just wait for the dollar to go up some more?

Well it looks to be not an N1 edition. The chassis number 304732 indicates a '93 model. The KBNR32RXFS7 is the same as the stoandard GT-R's, but the last two numbers usually read AA. Although it may be different for a 93 - the AA appears on the '94 FAST listings.... Bear in mind there were only ever 228 N1 built.

My opinion.... I for one would be asking some pointed questions of the bloke who sold you the seat. Like how hard he was hit when the car got pummelled on the passenger side. That seat looks for all the world like it was involved in a major side impact. Be careful before you use it for anything.

Spot on. I think that there is a bit of that going on.

Unfortunately you can (especially with turbos, but also with atmo motors with big cams) get large changes in TPS for small changes in torque output & even smaller changes in acceleration going up hills. Well that is the hard bit, really. Getting a single change made to the car & then testing it under the same circumstances. Even the data logging I have done on the circuit gives large variations in rpm changes (ie acceleration) depending on the ambient temps on the day. As often as not people make more than one change at a time. Certainly that is my plan at present as the workshop is two hours drive away from home. If your memory comes good please post the results up.

Volks are usually really good with caliper clearance. TE37's & CE28's especially.

So do they chafe your bollocks when you head out (ie when they are large) or on the way back after you have scared yourself silly? (ie when they have shrunk to the size of sultanas) I drove a Mazda with a 4 point harness. As I said the lap belts just rode up over my guts - hence if I did have a bingle all that would have happened would be that my spine would have snapped in half. No biggy but I thought a 6 point would prevent that. Looks like another hole in the floor. Goodo. More than one way to lose some weight out of the car.

Let me re-state that. My replacement car (same model etc) will be getting a lightened flywheel attached. Have I driven a cars with different amounts of inertia in the engine. Yes. Do I think the whole world should be on drugs to cope with psychological conditions? Well to be honest sometimes I think it might help. They weren't assertions. They were statements made off the back of a few simple maths calcs. If I have made a blue with the calcs (& I don't think I have) then fair enough, but otherwise what you are saying & what the maths is saying are two very diferent things. As a rule I trust the data more than the seat of the pants experience. Certainly there have been times where I could have swarn a change was for the better only to have the data tell me different. So I guess we are going to have to agree to disagree.

Well you are right in the sense that you need more throttle to achieve more rpm. I don't think that is much of a surprise to anyone. With a lightened flywheel you certainly don't need more throttle to achieve the same rpm, which is the point, really. Yes there is. Just because it goes round (at right angles to the direction of travel) doesn't mean you can ignore its effects in a straight line, ie it still acts as mass. Well if you re-read what wrote you will see I was describing a situation where the car is accelerating in gear - the dumped clutch off the line is slightly different & I described that differently. What you are saying in item three is correct for a start and or a gear change. Well I don't think I did, but anyway. As I explained there are two distinct situations - ie the clutch dump/start from standstill & then the mashing the throttle when already in gear. With a lightened flywheel you need more rpm off the start to get the same launch (due to lower rotational kinetic energy). This can be seen as more throttle, but it is only sort of more. You still need basically the same throttle position for the same rpm - you just need more rpm. The second circumstance ie in gear acceleration you definately need less throttle with a lightened flywheel. This can also be characterised as the amount of throttle needed after the clutch has been dumped. I thought this was what the bloke was asking, but I may have misinterpreted it a bit. I think we basically agree with each other. Just placing different emphasis on different circumstances. Good to see people making sense without resorting to abuse.

I was looking at the fat arse version (I have child bearing hips, all the males in my family have them) of the GP90. They have the benefit of being made here in Oz. Which is always nice. They are a damn fine seat. I assumed the bottom two belts on a six point harness would go through the base of the seat & fix to the same anchorages as the lap belts. Or have I got this wrong, too?

I will try to explain why I disagree with you. Please don't crack the sh!ts if some of it sounds condescending, but I guess other people may read it also. Anyway we have basically two forms of energy of motion. Potential energy. Kinetic energy. Now potential energy is simply energy stored by gaining height. It is equal to mass times height times gravity. ie E=mgh. Believe it or not we can largely ignore it, but we wont. Kinetic energy is the energy stored in motion of a moving body. For a linear case (ie straight line) it is equal to half the mass times the velocity squared. For a rotational case it is equal to half the moment of rotational inertia times the angular velocity squared. As you can see the linear & angular equations are expressed in a very similar way - basically because they are very similar equations & are derived the same way. Now to our case of going up a hill. Assume we are in 4th gear going, say 100km/h. We go 10 metres up the hill (vertically) & accelerate to 110km/h going from 3000rpm to 3100rpm at the same time. The numbers aren't particularly important, but they make it easier to understand. So what happens to our three types of energy? Well if we go up 10 metres we gain 10 metres worth of potential energy. So 1500kg times 10 metres times 9.81 which is the gravitational constant. So that increases by whatever the sum works out to be. What happens to our linear kinetic energy? We have gone from 100 km/h to 110km/h. So we now have 0.5 times 1500 times (110 squared - 100 squared). Technically it should be expressed as metres per second, not km/h but I am not going to work it out, so it doesn't matter. We have a gain in linear kinetic energy because we are now going faster. What happens to out rotational kinetic energy? We have gone from (say) 3000rpm to 3100rpm. So we now have 0.5 times the rotational inertia of the whole drivetrain times (3100 squared - 3000 squared). Again angular velocity should be measured in radians per second but I am not going to do the sum. We have a gain in rotational kinetic energy. This energy is provided by the power of the motor, obviously. This will equal the potential energy gain + the linear kinetic energy gain + the rotational kinetic energy gain + whatever frictional losses we have (eg aero drag etc) So how does a lightened flywheel effect the three sums? Potential energy. Well the gain in potential energy is slightly less because the mass is less. Linear kinetic energy. Well the gain in linear kinetic energy is slightly less because the mass is less. Rotational kinetic energy. The gain here is less because the rotational inertia is slightly less. What does this mean? Simply that the car with the lightened flywheel needs less power to accelerate up a hill than the same car with a heavier flywheel. Less power = less throttle. Why it may feel different. Simply because as you said when you drop rpm on the motor (eg when you launch) there is less rotational kinetic energy to turn into linear kinetic energy. So the motor feels more "gutless" on launch. Which is where I think alot of people get a bit confused. Lastly. My new car is due to be unloaded Monday. When it gets to the workshop I am going to fit a lightened flywheel - and use less throttle getting up the hills around home!

Well they are the other two problems. Because my thing isn't as race orientated as yours & becasue I have to travel a bit to get to the circuits I wanted to retain the normal belts. I have seen this done with fixed back seats but you have to be a bit careful in the selection. Not sure how to get around the side mount/seat buckle problem, however. Submarining is why I don't want to use a 4 point harness. I find they ride up on my guts too easily (maybe my guts wobble too much over the bumps or something) hence I wanted to use a proper 6 point harness. Hell if you are going to be strapped in you may as well be STRAPPPED IN.

Mmm, the bolts in the Moonface kit for the front end didn't look anything special. Maybe I need to look again. The manual does have a cryptic note on page CH-228. See attachment. Oh and Andrew if you are after some rear spacers I have a pair at home (2nd hand) for sale.

Well fair point. I was working on the idea that I would fit a harness & seat to my new car. Unfortunately it looks like I will have to do some more work as I want to keep the lap/sash arrangement as well as a harness. The buckle being attached to the seat frame complicates things if you want to replace the frame with a fixed side mount system.

You may want to detail what the stamp duty rates etc are as they vary markedly from state to state.

I can't offer an opinion as to which tyres are best on the track, but I can give you a bit of an idea of what to look for: 1. Stiff sidewalls. You will get more body roll on a street tyre than on an R compound tyre. Stiff sidewalls help prevent this. 2. Fewer circumferential grooves in the tyre. Basically the tread blocks will chunk on the tyres if you are having a good go on the track. They tear away from the outside of any tread blocks. Therefor the fewer "outsides" you have the bettter off you will be. 3. Don't worry so much about compounds. But nonetheless the hardness of the treadface is an indicator. You tend to damage them more by chunking them than by wearing them. Not to put too fine a point on it road tyres are a bit of a disaster on the track. You will have much more fun if the budget can stretch to a proper R compound. or even some of the less sticky half house measures like the Falkens which feel ok but don't deliver the lap times. Lastly if you are going to the track get yourself a good pressure gauge (Not a ghey one from Supercheap or wherever) & a pyrometer. By measuring the tread temperature at three points across the face of the tyre you can determine the correct pressure by ensuring the difference between the outside & the middle measurement is the same as the difference between the inside & the middle. You won't get all three the same on a road car simply because it wont have enough -ve camber.

I am going from memory here, so I may be compeltely wrong. (As opposed to not going by memory & being completely wrong anyway, which happens to me a lot these days) Anyway if you look at the bottom left hand corner of page BF70 of the R32 Gt_R manual. It replaces the anchor bolt on the seat buckle which goes into the seat rail according to the drawing. You probably have a point about the location, but they never seem to have a problem with the lap sash done that way...

Hmm, I will take a proper photo of my car & post it (after easter). But as I said the eye bolts just go in place of the usual retaining bolts. On both the outside & the inside.

Good will check that out. I was wondering more so how people anchor the shoulder belts, not the lap belts.