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20 Jul 2010, 03:04 (Ref:2729432) | #126 | |||
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the only reason diesel is ahead is because the aco is favoriting it because of audi and peugeut marketing!!!!!!!!!!!! a 5.5l diesel in audi and peugeut makes ~700hp that volume petrol engine with a twin turbo would make 1000hp easily with the same restrictors. so would you be so kind as to eplain how the diesel is better! when you are compering a 4l N/A petrol to a 5.5l Twin Turbo, with larger restrictors off caurse the diesel will win, |
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To launch a new FIA GT2 category based on strict technical rules, with limited wavers and ‘balance of performance' limited to success ballast. A category where GT manufacturers will prove through competition they can produce the best road going GT car. |
20 Jul 2010, 03:17 (Ref:2729434) | #127 | |||
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as for the diesel being a better fuel chemicly, from your statment above you proved your self wrong. because that small f1 engine with 1500hp, would leave the diesel prototyes so far behind that it could go into a pitt refuel, change the tyres, and the driver and let him have a cup off coffie and still lead the race, at le mans that is, do you have any idea how much of an advantige 1500hp woulg give anyone at le mans, that would be like 10-15s a lap |
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To launch a new FIA GT2 category based on strict technical rules, with limited wavers and ‘balance of performance' limited to success ballast. A category where GT manufacturers will prove through competition they can produce the best road going GT car. |
20 Jul 2010, 09:13 (Ref:2729515) | #128 | |||||
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Because you have been a Golf owner, perhaps the previous Golf GT is a good example. VW made the car with a diesel and a petrol engine:
Guess which car is faster. These are the performance numbers for the DSG gearbox:
Finally, the fuel consumption numbers, again for DSG gearbox:
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20 Jul 2010, 13:39 (Ref:2729611) | #129 | ||
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I don't know where to begin...
Diesel engines are more efficient than petrol engines due to the fact that they can run higher compression ratios than petrol engines due to the onset of knock. Using idealised Otto and Diesel cycles at the same compression ratio, a petrol engine is more efficient Diesel doesn not "literally explode" inside the cylinder, it slow burns, hence the lower engine speeds. By contrast, petrol combustion is always a very short process even when ignited via compression rather than spark ignition. This is due to the volatility of petrol and is also the reason for the compression ratio limit. compression ignition petrol engines can run to high compression ratios, the problem being that as the combustion is very short, the intake conditions need to be controlled precisely to avoid detonation or misfire. The noise of petrol engined LMP cars has nothing to do with burning petrol in the exhaust (how could this happen anyway given petrol's short combustion time?) but is due to the items placed in the exhaust. The diesel LMPs are turbocharged, which has an effect in quietening the engine noise and the particulate filters further quieten the sound. It's worth noting that the Peugeot is now almost as loud as the turbocharged petrol LMPs after allegedly removing their FAP filter. The diesels dominate LMP racing for 3 reasons: 1) they were given a massive advantage in the original regulations, 2) as diesel is a new technology to endurance racing, the development scope is greater, 3) factory teams always beat privateers due to their larger budgets allowing more development. Case in point, in 2009, the top petrol non-factory car was the ORECA, which completed 12 fewer laps than the winning diesel. In 2003 and 2004 against factory Audi supported opposition, the top privateers were 17 and 18 laps down respectively. |
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21 Jul 2010, 17:14 (Ref:2730244) | #130 | |
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All of this effeciency is boring the **** out of me.
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21 Jul 2010, 20:41 (Ref:2730338) | #131 | |
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You got that right!
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21 Jul 2010, 23:18 (Ref:2730389) | #132 | |||
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Isn't it that in order to achieve higher RPM, the motor has to be more balanced and to better achieve that a less energetic power stroke is welcome ?. Transmission have a "reduction ration" and a "multiplier ratio"... reduction is when the transmission output shaft has a lower rev ration compared with the "motor" input shaft. Its only there to REDUCE THE LOAD on the engine and permit a faster transition to more RPM and power... "multiplier ratio" is when the output ratio has more revs compared with its input... in order to sustain higher orders of "SPEED"... So its logic that higher RPM, 8K RPM or more, need higher reduction ratios to make easier and faster to achieve those levels, than an engine that has half the RPM for the same power envelope... Quote:
sorry i can't resist... why wont they invest in them then ??? Perhaps because that was when the F1 cars were below 500Kg... you have a hard time getting this... those engines wouldn't last a 3h race, and would consume a full tank every 7 laps in Le mans... so they would have to be considerably faster than the best diesels now to have any chance. But now if you put almost the double of weight and by doing so, almost the double load on the car engine, i'm very doubtful that those engines would be able to attain those levels of power... not even close by a long shot! actually diesel is not better chemically than gasoline, race grade gasoline for that matter, though even ACO claims that diesel has more 10% BTU per volume of fuel... the reason for the 9 liter less tank rule. IMHO it misses rigorous testing but the BTU is identical, though i can accept a tiny little advantage on diesel. Where diesel is far superior for a ICE is in its physical proprieties permitting much higher order of compression without self detonate... "knocking"... and so much better thermodynamic efficiency. |
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21 Jul 2010, 23:58 (Ref:2730398) | #133 | |||
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which is a lie of course... unless diesels where running JP8 kind of aircraft fuel which is very doubtful for a lot of reasons... Now that tells a lot of who is favoring who, dosen't it ???? Quote:
But in here i'm on your side believe me... there shouldn't be any discrimination neither in weight or in engine volume and restrictor sizes accounting only for the fuel type. Only then we would have a fair match = oranges to oranges = .Those diesels allowed to enter as they were, were a busted campaign to show the superiority of petrol that went the other side... to counteract the flight of general population to day by day diesel cars by economical issues... otherwise they would never had allowed them. And IMHO diesel now don't need any favor now. Petrol had a century of development in race conditions, diesel only 4 years... but its not to hard to see that the RPM potential of diesel will go high now that some fundamental issues of how they operate in race conditions are understood. Now the petrol head campaign, on behalf of scum "oil" lords and there big oil companies is in the sense of abolishing diesels... because if common people start to see the picture and wiseup, most of the cars sold would be diesels... even road "sport" super cars... and that could mean 20-30% less in their(oil companies) business volume ( an enormous amount of money!)... But fairness it not their motto... they would prefer to put petrol engines to shame to find that way a justification to abolish diesel than play really fair... and pretend by un-fairing every other rule that a large volume diesel is inferior to a smaller volume petrol engine, if possible... that is how scum the scum we are dealing with !... So never expect that no matter what type of fuel... diesel, petrol or alcohol... that ACO rules that engines main characteristics will be the same... scum "oil" lords wont allow them, only business nothing personal!... "we" people must not have tools to make an educated choice... |
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22 Jul 2010, 01:20 (Ref:2730410) | #134 | |
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If you are hear to talk about diesel petrol equivalency this is not the thread for you. This is the AUDI R18 Thread
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22 Jul 2010, 01:51 (Ref:2730420) | #135 | ||||||
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http://www.metacafe.com/watch/256724..._acceleration/ 81Kw ie ~ 110 HP " have it on good authority that the Peugeot engine has 84x82.5mm bore/stroke, 146mm con rod length, 14:1 CR " the rumor might be close to reality alright, but there was another rumor that stated that Audi had a 17:1 CR... now if you count the additional pressure of the turbochargers, that might give with 2 bar 28:1 and 34:1 respectively... Quote:
Where you get confused is this... " The peak power is very important for reasons I'll get to later, but the peak torque is essentially useless all by itself " which is very misleading; ... because it discards the action of the loads on the engine in any time. If the engine has no load, or negligenciable load, then torque matters nothing, give it a constant=1 and power is a direct function of the RPM of the engine... which is theoretically correct but describes nothing useful. If not a contradiction; .... because if You can't have one without the other. then how came one is all things and the other nothing. Hard time getting this : POWER = torque x engine speed, you cannot have 10 Nm and 1000HP unless your engine revs at 200.000 RPM( or much more)... but on the other side you can have 20000HP in only 300 RPM... yes 300 RPM !... in those 5 store high, big freight ships, diesel engines... those engines can rarely be said that accelerate, yet imagine their peak power ??? Simply you can't have power without torque... the better your initial specific torque, the better anything "power" related... only that max power attainable, as a number trowed on the table, is completely irrelevant when you pass a certain threshold. OTOH torque is always more relevant because the faster the car goes, the more the aerodynamic LOAD, and so the better the torque the faster it gets to those higher power levels and higher speeds. Quote:
But sorry to disappoint you, but i would prefer the TDI anytime, the money i save in fuel, will be enough, in 4 year after the guaranties expire, to transform it into a 300 HP "sport" car... the same cannot be done with the TSI, without marrying the daughter of a gas station company owner, to conclusion... and spend more money in the transformation, to begin with. Quote:
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Higher RPM is NOT ONLY achieved basically by "brute force"= more fuel, stressing more the engine, but much better by reducing in-balances in all moving parts and by reducing "parasitic loads"... your engine takes a lot of energy only to move itself = the bigger the engine the worst this might get=... petrol engines are better in here, diesel and others will catch up... you are laughing of yourself... Peugeot and Audi have started a little above 5K RPM, but already passed the 6K RPM in 2009 and 2010... and could had been more( perhaps above 7K RPM) if they weren't forced to restrict the engine more and more every year. Back to R18... i very much doubt, by these long dissertations, that Audi will go for Petrol with it. The passage to a V10, giving Peugeot the upper hand in torque, 5 power strokes per revolution against 6 power strokes for peugeot, should had been balanced by a better fuel consumption which was hardly noticed and a higher RPM ( a lighter engine )... a tough bet, remaining in conclusion to learn HOW and WAHT downsizing the number of cylinders will give you. So after this lesson learned is hard to believe they will discard it... and if it is a "winner" factory that goes electric-petrol hybrid is Peugeot... but which i doubt also, because they must know how electric motors are not good yet to balanced the losses by going petrol... and batteries still weight a "ton"... Last edited by hcl123; 22 Jul 2010 at 02:03. Reason: R 18 |
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22 Jul 2010, 05:01 (Ref:2730457) | #136 | |||||
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Stratified charge compression ignition... occurs at the boundaries of your fuel air charge and has a propagating front, and in here depending on the characteristic of the initial flame front your diesel can be quite a slow burner compared with gasoline. Same of those old engines even had a Glow plug always on to facilitate this... Homogeneous charge compression ignition (HCCI)... in here there is no flame front... sorry again, i know its a strong word, kind of explodes, that is, the air fuel charge simply ignites everywhere at the same time... http://en.wikipedia.org/wiki/Homogen...ssion_ignition this effect is hard to achieve and i don't know if that is the case of Audi or Peugeot diesels, but i'm not surprised if they managed to get that effect to some degree. So diesel by being, lets say, more energetic having more time to burn than gasoline in a specific volume of fuel, but by having the charge mixture much more compacted and pressured and so much more mixed, if they achieve a good effect of HCCI, then i can bet you that the same volume of fuel burns faster in diesel mode than in a spark petrol mode : practically there isn't a flame front in HCCI modes Quote:
In a way it has nothing to do with the pressure level... if it were possible to cool the air-petrol mixture while its being compressed, it could attain as higher compression ratios as diesel... with comparable fuel consumption and torque. As that is not yet possible, so petrol engines must always have a "flame front", the reason for the spark plug being there... and race engines with always very rich fuel mixtures, are "slow burners" compared with diesels that can achieve an ignition comparable with a HCCI effect... and simply at 8 to 10K RPM there is not enough time to burn all that very rich fuel mixture inside the cylinder... Quote:
I bet its the contrary... its by being turbocharged, and reasonably well... that diesel engines are more loud than they could be... pressure along the exhaust is higher, but particulate filters, like sniper rifle silencers, has had quite a job of making them almost inaudibles... and perhaps is what happened with peugeot , no filter/silencer and the sound got much higher... but i never saw a flame came out of a diesel exhaust pipe... Quote:
Reverse that... make everything equal.... I don't call it dominate... i call it crushing... there was a "oil-petrol" marketing campaign that went bad, happens often in all areas of activity... and in some way i advocate that the current situation is not funny for various parts involved... but the solution is not discriminate any kind of fuel tech by the way of very stupid distorted rules. Today constructors make multi-fuel engines more and more, and them tune them to a particular application... Let the rules for a ICE engine be EQUAL, and let the teams choose the fuel type without mioptic forced downsizing, cripitic stupid restritores regulation, and others. A Lemans car, prototypes included, must have place for 2 persons, and all cars must have road homologation and arrive at the "circuits" with those 2 persons ( one of the seats withdrawn for the race), from public roads by their own means, and so civil law must apply... petrol ( or diesel) noise must be only to a certain level permitted by law, filter/catalytic converters/ buffer silencers will be mandatories then, pollution emission regulations will also be mandatory. Then the constructors must make the best of an engine in any format( Otto, Wankel, rotary) up to a max of volume displacement no matter the fuel type... and restrictiors and weight EQUAL to all... according to the respective category. And Kinetic recovery systems allowed in any form or tech... meaning only that the initial electric power density and or initial hydraulic tank pressure, should be exactly the same also. Then finding out about a new prototipe like R18 will be much more fun... because they could decide to make something really exotic... and as hard this might sound, like with very small companies that are launching those techs in everyday cars, privateers could have more "guts" and launch simple and cheaper but clever exotic techs( by today standards) that might get them some luck. |
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22 Jul 2010, 05:05 (Ref:2730459) | #137 | |||
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L.P. |
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22 Jul 2010, 07:47 (Ref:2730490) | #138 | |
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Ok here goes my stance for the R18
Spider open concept 4 wheel drive with 4 small electric motor/generators in each wheel hub, perhaps in the range of 20 HP each, not more... A Litium ion battery pack that will allow to store the max amount of energy, in electric form as permitted by the rules Main engine a 3.7 Liter V8 biturbo diesel with double head camshaft and 4 valves cylinder, with a HCCI mode of operation integrated with the electric mode of operation, for low to medium RPMs, permitting a "soberb" fuel economy in those modes, to overcame the restriction of a much smaller fuel tank... Improved engine balance in its high RPM diesel mode, achieving close to 8 K RPM at max. Max power >=650HP, max torque ~900Nm It would be a clever trick!... the rules have holes and blanks... but 2 of the electric hub motors can be made to run constantly from cruising to acceleration, perhaps the front wheel motors with power generated and delivered directly from the other 2 wheel hub motors acting as generators on the rear axle, by-passing that way the batteries. Upon braking all wheel hub motor/generators will generate electricity to be store in the batteries. Upon medium to heavy acceleration all motor/generators will motor the wheels for an additional max power of 80HP and an additional max torque of ~180Nm. hints: VW had a concept with wheel hub motor/generators... 4 wheel drive is almost a trademark of Audi, and would permit to take better advantage of the additional torque of the electric motors |
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22 Jul 2010, 09:50 (Ref:2730531) | #139 | |||||||
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Audi has found out from racing the Peugeot 908 that closed car have an aero advantage. Next year, with the reduced power this will be even more important. See http://www.autosport.com/news/report.php/id/84533 Quote:
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22 Jul 2010, 14:16 (Ref:2730649) | #140 | |
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22 Jul 2010, 14:35 (Ref:2730655) | #141 | |||
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The hybrid rules have been changed for next year:
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Sadly, this is a terrible translation because the French version says: Quote:
So the hybrid system can work on the front axle or the rear wheels, but not on all 4 wheels. This allows for a form of 4 wheel drive: front wheels by electric engines and rear wheels by combustion engine. |
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22 Jul 2010, 18:43 (Ref:2730765) | #142 | ||
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22 Jul 2010, 18:46 (Ref:2730767) | #143 | ||
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No, it means that they can be different at each axle... you can have a Flywheel KERS at the front axle, while electric generators at the rear axle.. that is what i read. And account by that reading i cannot understand how 4WD can be excluded. " Maximum quantity of energy released between two braking phases to be 500 kJ. " Means that KERS or electric battery and or a hydraulic pressure tank, in the total they cannot exceed that amount of energy. If energy storage is that amount, additional energy release cannot exceed that point... yet it doesn't account for continuous operation from generation to motor, because if generation accounts for a certain loss, motoring upon that generation can never exceed the loss... if 2th law of thermodynamics is to be correct... otherwise ACO doesn't guide itself by the accepted physical laws. Funny thing ( those ACO guys are in disarray) " Other means of energy recovery will be allowed: exhaust, engine heat, dampers, "etc." provided that they respect the specifications drawn up by the ACO (safety considerations, banning of driver aids, evaluation of the increases provided by the systems, the reduction in fuel consumption and CO2 emissions)." Would make it possible to include the most efficient method of all, hydraulic recovery... transporting to day by day cars will open the way for Hydromechanical IVTs... providing a significative boost in fuel economy and efficiency(Honda as such a transmission in commercial motorbykes) ... yet " Energy recovery systems using brakes must not be active during braking for curves (driver aids banned)." Excludes the most significative way of hydraulic energy recovery, because a hydraulic pump/motor at pumping upon braking, acts as a very efficient braking auxiliary... or putting it another way, why would anyone brake if not for a curve.. in normal conditions... what are those guys smoking !!! The same goes for electromagnetic brake/generators !!!... gee!! ... how could additional braking action, be any different from a bigger and or more efficient traditional braking setup ???... the driver putting his feet on the ground to help braking is also forbidden( can't help himself)!... seems a greased scum is whispering at their ears... else they have coca and whisky parties at those meetings!!!... |
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22 Jul 2010, 18:49 (Ref:2730770) | #144 | |||
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22 Jul 2010, 18:50 (Ref:2730771) | #145 | ||
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L.P. |
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Probae esti in segetem sunt deteriorem datae fruges, tamen ipsae suaptae enitent |
22 Jul 2010, 19:32 (Ref:2730791) | #146 | |
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22 Jul 2010, 19:51 (Ref:2730798) | #147 | ||
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I agree. There have been a few people who have turned up/returned here recently, who seem hell bent on trying to impress the rest of us poor, uneducated souls, with their lengthy, waffling on responses, and I think we all know who they are and their history. We won't think any less of you, if you can keep it more concise. |
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Go the mighty Flying Lizards "A good way to gauge the strength of your argument is to weight the quality of the rebuttals. Strong arguments have low quality rebuttals." David Heinemeier Hansson |
22 Jul 2010, 20:13 (Ref:2730812) | #148 | ||||||
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20% is bigger than 10% Quote:
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That accounts also for traction control systems... are they abolished also ?... my idea of 4 in-wheel motor/generators is that they could work as a great traction control system as well as a ABS system, along with motor/generator action, all in the same system, and 4WD will permit better curve handling, acceleration and braking... ok driver help And what about electronic blocking control of the rear differential that Audi uses ??... is that driver help, if not, what is the difference in effect from a iso-torsen pure mechanical differential, and other possibly all mechanical traction control and ABS system ?? OTOH, a continuous motor generation action will permit to smood the attrition of the tires and suspension upon irregularities of the road, and in some situation, by the law of conservation of momentum, result in a net gain if energy recuperation upon braking would be allowed. Batteries would last longer and be in average more full of energy in all race conditions. ( otherwise -supercapacitors the petrol way) " Energy recovery systems using brakes must not be active during braking for curves (driver aids banned)." this must be the joke of the year... next they will withdraw the driving wheel because that is a driver aid!... go for mind control steering systems instead... only misses this one.. No wonder some privateers are **** off ?... this guys make rules out of the toilet can... that can only make costs to skyrocket. Quote:
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22 Jul 2010, 20:15 (Ref:2730813) | #149 | |
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than the english translation is kind of wrong
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22 Jul 2010, 20:24 (Ref:2730819) | #150 | ||
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Hard to believe they risk to make the same mistake again. |
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