hrd-hr30

I love OT nazis. Mate, the thread topic is "R35 horsepower figures", nothing to do with weight.

you also have to remember that torque is not an energy, its a force. and helical cut gears lose a % of that force in a different vector. this loss doesn't go directly to heat, its absorbed by the housing or carrier. I think doubling the engine power would almost double your drivetrain loss. Its a pretty good approximation anyway. Certainly alot better than a fixed value loss. eg if you make almost double the torque to double the power as you can do with a turbo car if you have to then you've definitely doubled amount lost through the helical gears. and they will try to push themselves and their housings apart, or in the case of difffs the pinion will try and climb the crownwheel. On the other hand, if you almost double your revs to double the power, you probably will loose that extra 25kw in heat through frictional losses. If you double the power with some combination of the two (torque and revs) as is the case most of the time in the real world, then you'll loose parts of the increase to each - some extra lost force vector and some to heat. Mind you, you're not at that full power very often, so those extra 25 1kw heaters are only all on at the moment in time you make that peak power figure. The more you're at and around that peak power, the more heat you'll make. hence why serious race cars will have oil coolers on boxes and diffs as well.

percentage is the best approximation for drivetrain loss. helical cut gearsets in the box and diff(s) generate side loads proportional to the input torque. So you have a percentage loss there straight away. frictional losses (in engine, box and diff) increase exponentially with speed. % loss doesn't really model that, but its a hell of a lot closer than just calling it 80bhp loss. a simple straight bhp loss in the drivetrain doesn't do anything to approximate those factors. besides, I can turn a GTR gearbox and diff by hand, and even Arny wouldn't make 80bhp! my mates' Landrover Discovery turbo diesel only makes 85bhp and it manages to move a big heavy constant awd vehicle without any problems. amazing what you can do with 5bhp left after drivetrain losses hey?

only reason is that time attacks have street tyre and semi slick classes, and no full slicks. is there any reason it should be done different here? there's nothing unsafe about using road tyres on a race track. but if you think you have too much power for them, then stay on your semi slicks and run in that class. no problem. the point is its a much easier way to seperate the classes than trying to make your own rules based on levels of modifications. your case is a perfect example - a heavily modified car won't want to run on street tyres and therefore will be in the race/semi slick class. perfect. doesn't mean the street tyre class shouldn't be there for less modified cars. And if a heavily modified car were to run on street tyres, they'd probably struggle to beat much less modified cars that aren't overpowering their tyres, so they act as a bit of a 'leveller'. if the classes are going to be based on mods, then using an established set of rules makes alot more sense than trying to come up with your own. either Duncan's (I think it was) suggestion of using Production and Improved Prod rules or the Rev Speed rules. isn't that how the original time attack rules are - street tyres and semi slicks?

This is the guy I bought mine from about 5 years ago: Chris Wedding 5547 7394 or 0419 649 510 A Standard 2000 kg GTM Car Trailer has the following: - 4.3 x 1.9 load area (my R32 GTR just fit on there with an inch or two to spare either side), - disc override brakes or electric on front axle - spare wheel, - Jockey wheel, - Tare approx 540kg He makes a very good trailer and I doubt you'll find a more competitive price. I'd recommend 2500kg rated axles and springs though with a GTR - the GTM includes the trailer's weight so it really only leaves you 1460kg carrying capacity with the standard 2000kg GTM trailer. And go with override brakes - they're much better than electric. One last tip - never use retreads on tandem axle trailers - they will blow. Pay the extra and get some cheap new light truck tyres.

you can have mine for that! with trailer!

FIIK. Never seen or hear of Matty before now - even on the forums. But if throwing rocks from a safe distance is all the courage he can muster even in an anonymous threat, I'm not particularly worried. Matty, you can find me at the next hillclimb - not that you'd even know where that is. Don't dissapoint me now tough guy...

its all too hard to define a street car based on modifications. This is easier: street class - street tyres (>100 UTQG) race class - semi slicks jobs done. no controversy, no headaches for anyone with half a clue. I don't see why people who want to make sure they can run in street class don't want to run street tyres? so what if many of them already have semi slicks? I'm sure all genuine street cars also have street tyres. And if they don't, well maybe they should be in race class.

+1 for Lakeside! Far more technical and challenging. It requires a far more all round performing car than QR, which is all about power and brakes. And would be much more worthy of the interstate trip for the southerners too - its an awesome track. Noise restrictions will be tight though.

having built a couple of cars to IPRA regs, I'm very familiar with them. You should refer to section 17 to find out what doesn't apply to Late Model (1986 onwards) cars. as for 3.6. alot of road cars have front spoilers that would be illegal in IPRA. and 3.13 does not allow you to replace side glass with perspex, if that's what you're getting at?

like I said before most of those things are being done to road cars too - my comments in red. and I think alot of the cars hoping to sneak into street class have lots of those things. Needs to be simpler - ie breaking it down by tyre type. sounds good. no firewall mods and semi slicks will keep most genuine sport sedans out. Those built, or being built, to the new AWD Sport Sedan regs will be fine on appropriate tyres. That's a good balance.

yep, dud driving. how many mis-shifts? And certainly wasn't very agressive picking up the throttle. it looked alot higher and softer than I would have expected too! and talk about pitching under brakes! yuck. not really surprising that it wasn't being pushed too hard with them being made in such small numbers. I'm sure the owner gave strict instructions not to bend his irreplaceable car.

I think it does need a street class. only problem is everyone who is bordeline wants to make sure they fit into street rather than race - even if they've spent tens of thousands in "basic" mods on their "road" car. Massive brake upgrades often on hats, huge power increases, adjustable arms, adjustable shocks, adjustable height platforms, sometimes even cages. Not sure what more you could really do to a race car excpet a CR gearset? Only the highest level of circuit racing in this country allows lightweight panels & glass removal, so 98% of actual racecars don't even have them. Just because you retain an interior doesn't really mean that much. Harden up and go play with the big boys. Best way around it is to make street class run normal street tyres and anyone on semis into open class, because only those with the borderline cars will realy be put off by that - not many with those levels of mods will want to downgrade to street tyres with >100 UTQG ratings. And those that do will be brought back a fair way to the pace of genuine street cars. Too much power and stiff suspension on road tyres will need to be well driven to beat cars on more street oriented suspension and power levels on reasonbly tight tracks. That way the choice is theirs.

Never seen the value in Dutton. Nor the attraction - far too many 'khana style events. It would bore me to tears. QLD Challenge has 7 or 8 speed tests every year including up to 3 closed road 'special stages', normally only 1 'khana test, and the rest are on racetracks. All for around $140 entry. That's more like it!

I saw the power figure in your sig. 57.3 is a hot time for a rwd. specially a heavy one like the Z32. well done! I imagine PI would be a pretty daunting place first time there. we don't have anything like it up here to prepare you for those high speed corners.

isn't the whole philosophy of Time Attack is about using semi-slicks?

call me a cynic but I suspect NISSAN's marketing dept also 'engineered' their performance figure CLAIMS to be just a bit faster than the Porsche 911 turbo, which isn't their flagship performance car anyway. The only actual test so far got 4.0sec 0-100 which is slower than the Porsche. I call bullshit. where are you getting these figures from? what gumby was driving it? McLaren F1 467kW/630bhp 650Nm/480 ft-lbs 1140kg laws of physics are not on the GTR's side. GTR has over 100kw less power and well over 500kg more weight to lug around!

WTF's an Australian Shepard?

next time I do a wet event I'll bolt on my roadies just to demonstrate how much slower thay are. would have to be 2 sec per km conservatively. I can't believe people really think street tyres are better in the wet. Then again, I've met the odd bloke turn up at hillclimbs thinking their road tyres were the best thing to be on because "semi slicks won't get up to temperature". My guess is you've never competed on a street tyre in any conditions?

I guess you'll be using one of those "good road tyres" instead of semi slicks in the next cold wet Targa Tas then? You'll clean up! BTW - I wasn't using the super soft WT compound RE55S - the 'S' is just the later version of the RE55, not a compound. I just had the normal medium compound that was the Saloon Car control tyre (225/50*16).

it won't hurt your auto box, it would hurt the transfer case if anything and the operation of the AWD system. But 225/40 to 235/40 is bugger all difference in height, about 4mm. Even less with the stretch on the rear sidewalls. I doubt it will be a problem at all. mr plod will like them too I reckon, as will an insurance company if you have an accident with tyres fitted to rims outside the maximum recomended width. hopefully it never comes to that.

I think that's a good idea. It saves the headache of making your own rules, and anyone who has done any sort of actual motorsport is already familiar with the categories. You'd probably also want to allow aftermarket arms with rod-ends/rosejoints/bearings in Improved Prod as well- alot of late model JDM stuff run them, and you don't want a fast street car being in Sport Sedans just because they have an adjustable arm or two.

jeezus! he ran open class in Japan and came 13th outright, and that's only going to be street class here!!! wow

nothing about it being damp when they did it. If it was damp I doubt they'd say it would be hard to beat in normal conditions. so my point about knowing how to drive, or getting familiar with the car helping accelleration times significantly still stands.

mate, I don't think this is the place for re-hashing that, but feel free to correct anything I said in the earlier post that was not 100% accurate and truthful. I only mentioned it because it seemed relevant as a heads-up for Giant to help prevent anything like that happening at his event/s. I liked the rules - you could tell because I wasn't one of the blokes who broke them. And I deliberately didn't mention what event it was and didn't name any names or anything, but you still feel the need to jump in. Well, since you brought it up - did you not realise that you were buying semi slicks from the Kuhmo Motorsport distributor??? I can understand that - its an easy mistake to make... As long as you feel you won fair and square by not entering the class for semi slicks, that's all that matters Wilo. And just for the sake of accuracy I was the one threatened with defamation action. I didn't threaten anything. I told him I'd take it to fair trading and I did. They couldn't proceed because he didn't provide a reciept or ABN, so I had no proof any transaction actually took place. that's all you'll get from me on that subject. sorry to go off topic people. ps- link to thread as requested by Wilo http://www.skylinesaustralia.com/forums/Aw...hl=awd+shootout