high revs engine

[roospuppet]

hi there, just wondering wot i would need to make an engine an extremely high revving one, i no u have to reduce friction, in an engine, use a dampner for the torshional vibrations on the crank, and get a dam good g box, but have i missed anything

cheers


ian

[roospuppet]

would a rotary valve be the way to go, www.coatesengine.com
that would reduce valve train, and yes building an engine from scratch is teh way, thinking of tryin to do summit like teh old f1 turbo engines, really small piston, maybe 50mm bore and a 50 mm stroke only estimates, but this is similar to the f1 turbo engines, with as many pistons as possible,

>> Edited by roospuppet on Thursday 19th December 15:54

[roospuppet]

the point about the honda s2000, im sure they could have mad eit rev higher, but low end torque would have suffered and remeber they have variable valve timing, which is probly not as strong as the normal valve actuation system, they had to compramise with perfromance and fuel economy, and i fink they did very well , 237 bhp from a 2 ltr, and stil gets resonable mpg. thats variable valve timimg for ya,

[roospuppet]

can u explain nvh patterns please

[roospuppet]

im after a combination of torque and revs, lookin into various ways of makin engines, will take a long time doing, i am studying mechanical engineering at the mo, and havnt covered the full sylabus yet. so my knowlege is far from perfect, but im still learning, my aim is to have an engine perfect for a light weight kit car, ie lighter than 500 kgs, just considering, the perfect match,

[roospuppet]

coates engines wont actually produce anything with other companys at the moment, they are into heavy diesal engines, but in the futute they may consider doing such a project

[roospuppet]

also there are many designs for a rotary valve, but teh coates seems the best , because it seals the cylinder better than any others,

[roospuppet]

good point, so u reckon tvr should cum up with there own design, cos i have my own design , which is similar to the coates design, which wil lbe heavier but more efficent, but not that much heavier,

[roospuppet]

grahambell said: Hi roospuppet,

Considering this thread and your other about rotary engines I have to ask this - what's the obsession with high revs?

my obsession, about revs,is that revs is proportional to power, torque can be increased with a g box, so maximum torque is not so important at the engine,but at wheels where acceleration cums into play, so the high levels of torque (at wheels) can be acheived for a longer period with higher revs. so maximum acceleration, acheived through high revs, with a cleverly designed close ratio sequetial g box, that has computer controlled gear changes, which happen ina fraction of a second, the car would be extremly fast, ie f1 car fast, even though f1 cars only do 0-60 in 2.16 secs, they carry on going,
of course this car would be quite rough to drive on road at slow speeds, but u just tell the comp to choose a higher gear, for road use

>> Edited by roospuppet on Saturday 21st December 12:01

[roospuppet]

well basically teh high gear, ie 6th gear in the high revving engine would be roughly the same ratio as a standard ford escort's second gear, becuase of teh such high revs, and this engine will still ahve alot of torque due to the 12 cylinder and possibly a turbo, not sure bout turbo yet, but still the (2nd gear ratio) 6th gear in this car, would still be at 200 mph, full revs, on a rolling road,

[roospuppet]

so basically teh very low ratio of gears will increse teh toque, plus the point about wil lhave very poor low rev performance, say u was doing 30 mph, u get the comp to put it in 1st gear, and bam ur away, cos of teh light weight, it will just fly, buti need a cleverly designed computer controlled clutch and gear selector, although clutch will onyl be used to pull away initially and driving at low throttle, the computer will take it out of gear let teh revs fall to teh level at which he engine revs are the same as teh speed of the new gear, for teh road speed, (cor im confusing myself, but hopefully u will inderstand)then pop it into gear, and for change downs, the comp will increase revs, to the rite speed,and pop it into gear,


will need quite a good set of phematics for this,

[roospuppet]

500 kg car
revs 16k rpm plus
turbo
0-60 in summit stupid,
over 1000bhp,
v12 probly, very short stroke, around a 3 ltr,
top speed around 180 mph is sufficent, it depends on teh aroedynamics,

basically, i have never heard of a car like this, if anyone has done a car like this, then i wanna shake there hand, then go for a drive in it,

one problem i will face is sound emmisions, maybe a bit of trickery will help, only tuning the car to bout 6k rpm, with a silencer on, get it through the test, then take it all of, reprogram the computer, and wow, 0-60 in summit stupid time, under 3 secs,


not sure whether to consider carbon fibre the frame, which wont be very safe, but it will be light, or to make it out of steel and crygenasise it and turn it into a marsenite,

[roospuppet]

[quote
yes - carbon chassis are notoriously unsafe - look at the recent deaths in F1. Oh hang on, they are safe! silly me.

---

but wot about side impact protection, isnt carbon fibre only strong in one direction, so a very clever chassis would be designed, weighing a bit more, but probly still less than a steel or other metallic chassis

[roospuppet]

isnt it in teh regulations of f1, that they are not allowed traction or launch control, they did used to have traction control, most teams had a 1% error, from front wheels to back, the trction control was run from a petrol cut of, it was so effective becuase of teh light engine parts the revs and power could be taken of quick, that when wheelspin was detecteded, it was instantly stopped, renault actually had such a good system they allowed 3% slip,


im sure the car would be drivable, on teh road, u just pull away ina higher gear,let teh computer decide wot is approriate for eth amount of throttle pressed down,

launch control could be designed that the wright amount of torque at the wheels could be applied, with a electronic controlled clutch, and throttle limiter,(electronic throttle)


although would thsi be illegal on teh road, i will ahve to read through the sva.pdf to check, becuase if teh clutch and throttle was controlled by electrics, if they messed up,then ur the car could go for a joy ride by itself, lol, how much fun would that be, with only the steering u control, and brakes that have no effect on 1000bhp


lol

[roospuppet]

electronics are much faster in reacting than humans,they can also detect small errors, and correct them b4 a human has even detected a bit of slip of teh road wheels, thats why drive by wire is so good,


a comnputer would also be good at steering a car on a track, becuse every possibility could be accounted for, but obviously not on teh road,

[roospuppet]

does anyone know of any coatings to piston and other parts the engine , ie cylinder walls, and bearings. that reduces the friction, because if u can have a low co efficent of friction then it allows u higher bhp,and less stress on th eengine,
i have heard of coatings that reduce friction, but idealy u need a coating with the abilty to not conduct heat to, so minimal power is lost in the combustion process, so if there is a coatimng that does both, that would be perfect

[roospuppet]

i heard of ptfe before, the problem is, i cant seem to find a coating that will reduce friction and stop heat conductance to the piston, some ceramics have these propertys but they are brittle and crack, and the strength is has something left to be desired, ceramics would be perfect for fuel economy car, but not performance,

[roospuppet]

blue printing, do u mean better drilling and finishing of teh bore and pistons, so a tighter fit is possible, i heard that cryogenics, reduce friction of teh engine and increase streght, but does it reduce friction as well as a coating,



cryogenics, process of freezing metals to turn them from a austenite to a marsenite, ie arrange the atoms in a ordily fashion

after the cryogenic freezing i fink teh block can be bored to a better accuracy and pistons made better too, so a closer fit is possible

>> Edited by roospuppet on Monday 30th December 21:18

[roospuppet]

thakyou grahambell, i have looked into that link, and am very interested in the book, when in comes out, i have been away gettin costs and estimates for such an engine, need to save up a few student loan cheques, lol.

also tryin to find an autoclave for the makin of carbon fibre, is teh autoclave nessary, do u need the high pressure, can a kiln just do it, obviously it wont be as strong, but a lot cheaper,

i think i am going to do a cheaper project before i undertake this one, fiting a 2.9 24v cosworth lump ina mini, am tryin to do it with the aid of carbon fibre, btw im a mini fanatic, am a tad crazy too, b4 u say it can be done, and has been doen b4, its just the finished product wasnt so light it nearly weighed a tonne due to teh roll cage and strengthening of teh chass, with tubular steel, i want one that weights half that, around 500 kg, mmmm,