|
#91
|
||||
|
||||
|
Quote:
I'll do the math with my BP petrochemicals friend tonight over a beer -- so no guarantees of accuracy ![]()
__________________
Voitures-Françaises 'R' Nous ( そして日本語 ) und jetzt der neue Ringmeister "Thank god I am not -What-" |
|
#92
|
||||
|
||||
|
Quote:
*chuckle* Well, let us know how that works for ya. |
|
#93
|
||||
|
||||
|
fark, ok this is one helluva convo, ive just read page 1 through to 7, and possibly 30% of the terminology and concepts i understand. Matra ya bastard, i envy your intelligence and understanding of cars
![]() Btw, back on topic (well the thread title) It's an interesting concept that I hope comes into at least (small) production to show the world its potential and further development if it were provided with more funding. There is always room for improvement in an engine, and simply bagging it in current stage wouldn't be justifiable if there are already plans for improvements with fuel efficiency and what not.
__________________
House said the perfect woman was a man...now im all confused!! What is a mile long and hasn't had sex? - The line for the PS3 |
|
#94
|
||||
|
||||
|
who said use water cooling to replace radiator ??water cooling will cool the intake charge, it doesnt remove heat from the block and engine parts
|
|
#95
|
||||
|
||||
|
development in current combustion powered engines i think is a stupid concept, we're gonna run outta fossil fuels soon, thus it wont warrant more development into something we wont be able to use into the forseable future, better invest in hydrogen power, and electric cars which can last longer then an ipod and without battery problems
|
|
#96
|
||||
|
||||
|
Quote:
Quote:
__________________
Stop pouring petrol on yourself and it won't be so tempting :D (C)2007-MatraetAlpine "Thank god I am not -What-" |
|
#97
|
||||
|
||||
|
Quote:
![]() there are very few untapped oil fields left and there aren't any new ones being made anytime soon
__________________
How can men use sex to get what they want? Sex is what they want. - Frasier |
|
#98
|
||||
|
||||
|
Quote:
__________________
Stop pouring petrol on yourself and it won't be so tempting :D (C)2007-MatraetAlpine "Thank god I am not -What-" |
|
#99
|
||||
|
||||
|
Quote:
__________________
How can men use sex to get what they want? Sex is what they want. - Frasier |
|
#100
|
||||
|
||||
|
Quote:
__________________
Stop pouring petrol on yourself and it won't be so tempting :D (C)2007-MatraetAlpine "Thank god I am not -What-" |
|
#101
|
||||
|
||||
|
under current consumption patterns and rates this estimate MAY be true, but developing countries are increasing their ussage of fossil fuels and such to maintain/increase this growth, as a result of getting richer they'll also buy cars
you could argue that cars are becoming more efficient but imho i dont think that they'll become mainstream quick enough to do any measurable good all of this is besides the point since we know that the supply of fossil fuels wont last forever so why not get an early start on an alternative hopefully renewable and non poluting fuel ?? |
|
#102
|
||||
|
||||
|
Quote:
Quote:
Bruce Crower (I'm sure you've heard of Crower internals) has invented a highly efficient single cylinder 6-stroke gas/steam engine. Not only does the water injection/steam help make the fuel last longer, but it helps in the cooling process as well. The engine doesn't require a radiator. |
|
#103
|
||||
|
||||
|
I just read this whole page from 1 to 7, and can't believe what I am reading. stian1979 is the only person here that understands what's happening here.
The revetec engine is equivalent to a conventional engine with a 3:1 reduction built in to it. If it's output shaft is doing 3,000rpm, then it's camshafts, valvetrain, and pistons are doing an effective 9,000rpm. Therefore it looks impressive to the untrained eye. If you don't believe the 3:1 thing, then just look at it. On a normal engine the crank runs the camshafts at a ratio of 1:2. If you have 10 teeth on your crank pulley, you have 20 teeth on your crank pulley. Because the revetec is a 3-lobe design, it is like having the output shaft (crank) geared down 3:1. So you need to gear the drive to the cams back up 3:1 to get the same piston and cam cycle ratio. So you basically need to have 3 x the normal 1:2 ratio. Or a ratio of 3:2. So if the crank pulley has 30 teeth, then the camshaft pulleys will have 20 teeth. Quite the opposite to the normal engine, and look, it does!!! ![]() |
|
#104
|
||||
|
||||
|
So what does the 3:1 ratio mean? It means they are cheating in some of their marketing.
Take their latest engine test results; http://www.revetec.com/files/Announc...2004.05.06.pdf The engine they specify is 1.38L. 94mm bore with 50mm stroke. That bore and stroke on a conventional engine gives 1.38L, so they are not compensating for the 3:1 ratio in their effective volume calculation. So they have tested the engine and get 57kW@4,120rpm. With the effective 3:1 reduction taking into account it is really doing 57kW@12,360rpm. And they get 140Nm@3,650rpm. But because of the 3:1 ratio they are really getting an effective 47Nm@10,950rpm, and then gearing it down so it looks more impressive. It's false advertising really. And those effective rpms are correct, because that is what the piston speeds and valve train speeds are equivalent to. Now they compare their relatively high performance engine (Haltech injection, custom made everything, probably individual throttle bodies) to a low performance production toyota engine. That's not very fair. They then say "Not only are we producing the same power with a smaller capacity engine, but we are doing it at a lower rev which saves fuel. We also are producing more torque than the Prius at a lower rev with a far shorter stroke." Lower rev so it saves fuel? what a crock. That is so misleading. Because the revetec pistons go up and down 3 times as much, it will induce 3 times as much air into the engine, and therefore use 3 times as much fuel for any given rpm. But why not compare the revetec 1.38L engine to a conventional engine in a similar state of tune? One that revs to around 12,000rpm? Well that would be something like the Kawasaki ZX-14 engine. It is 1.35L, it makes about 140kW @ 10,000rpm, and about 160Nm at about 8,000rpm. These figures absolutely embarrass the revetec motor. There is no comparison at all!!! Or the other way to look at it is to compare a ZX-14 running through a 3:1 reduction box, and the revetec. So the ZX-14 would now be 140kW @ 3,333rpm, and 480Nm @ 2,666rpm. Compared to 57kW @ 4,120rpm and 140Nm @ 3,650rpm. Can you people see the difference now??? That shows the revetc is working harder than the ZX-14 engine, and making way way less power and torque! |
|
#105
|
||||
|
||||
|
Quote:
__________________
People are like slinkies, they are completely useless but still bring a smile to your face when you push them down a flight of stairs. |