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TORQUE not BHP
Hobnailkelly:
There aint no substitute for CC's ...
extreme90:
or as ive said before :P
get a diesel aka a tractor engine
no bhp
but a kin massive flywheel to store a load of energy and give u zillions of ft lb's of torque
all at idle
now 6000rpm and coughing and spluttering like your v8 :tongue: :tongue:
ps u upsilverdale sunday ad ?
dan
Xtremeteam:
2 secs
let me find the link to a small diesel engine thats quite torquey
Xtremeteam:
http://people.bath.ac.uk/ccsshb/12cyl/
5,608,312 lb/ft at 102rpm :twisted:
disco-v8:
--- Quote from: "thermidorthelobster" ---They're actually two sides of the same thing, and they're directly related by a formula.
1 HP is 550 ft lb per second.
What does this mean? It means that 1 HP has the ability to move something 550 ft per second against a force of 1lb. So if you had a 1lb bag of sugar on the end of a string, and you had a 1HP winch, the winch would be able to move the bag 550 feet vertically (against the force of gravity) in one second.
Alternatively it could move 550lbs of sugar 1 foot, or 1100lbs of sugar 6 inches, etc. (You can also substitute other things for sugar - flour, salt or other cooking ingredients all work :) )
In a rotating engine, the engine also turning a certain number of revolutions per second (or minute). This means that power can also be related to torque and the rpm of the engine.
Specifically, power is torque x the engine speed in rpm, but we also have to multiply by a constant to convert from seconds to minutes, and allow for 1HP being 550 ft lb, not 1 ft lb. If you do the math (this describes it quite well) you find that power is torque x rpm divided by 5,252.
So say your engine outputs 200 ft lb of torque at 2,000 rpm, you can say that the POWER of the engine at 1,000rpm is
(200 x 1000) / 5252 = 76hp. But this only holds AT 2,000 rpm. When you see HP quoted for an engine, it's always the MAXIMUM HP across the whole rev range.
Now, you'll notice that for the same torque, the higher the rpm, the higher the HP. If you had 200 ft lb of torque at 4,000 rpm, ie the same torque, the power would be 152HP. This is why peak power is high up the rev band.
This is also why people talk about torque as 'low-end grunt', and power as high-revving power. Because power only becomes significant at higher engine revs. If you had a totally flat torque curve, the max power would always be at the high end of the rev range.
If you're sufficiently bored, you can take a tuner's torque curve and do the maths, and work out what the power curve for the same engine is. Do this and you'll actually invariably find that below 1,000rpm they exaggerate the power! If you plot torque against (power / revs) you should get a straight line... but you never do, because they fix the graphs.
You can also see that if you do something which changes the TORQUE of the engine, by definition you also change the POWER, but only the power in that part of the rev range where you've changed the torque - which isn't necessarily the max power. If you change the torque at higher revs, then you're boosting the power much more strongly that if you change the torque at lower revs, so high-end torque boosts will mean the max power is likely to go up, whereas low end torque boosts won't unless the torque curve is affected quite noticeably.
Does this make any sense?
--- End quote ---
thanks with that one i think thats the best answer ive got so far BUT!!!!!! its not exsactly what im asking......
with the answer you've just put im more sure ill get a proper answer from you...... everything you just wrote there i already knew, even though it took a while for me to understand at first when i first founds out about it....
i know what i want to say and ask but its hard to put down when your on a computer and its seems thats its coming out wrong!!!!! basicaly i know what TORQUE is and BHP is, and like i said at first i dont believe in BHP as its just a figure made up from TORQUE
ill try a bit harder this time to get my question out properly.... ok forget its a V8 like mine just imagine its any engine, petrol or diesel i dont realy care. like you just said racing engines usualy have loads of cam over lap to increase the air flow, so wot sort of cam would a torquey engine have???? BUT dont forget im not just asking about cams, i want to no everything that differ from a high BHP engine and a high TORQUE engine and please please dont come up with the usual stuff that kids already no of.....
im the sort of person who understands all about MAPS, batch injection firing, ignition timing, that you need 1 cubic meter of air per minute to abtain 1BHP (yeah work that out in a high powered engine), injection spray pattern, why sraying fuel on the back of a valve is good, compression ratio's, pinking, air flow, longer and shorter inlet manifold vary power, differnt size tummpets give different air ressornacies which vary air flow ETC..... all that simple and very understandable to me....
BUT i just dont understand what factors including some of them from above change an engine from a high BHP 1 or a TORQUEY 1
ok just thought of another exsample.... a 3.5 disco/RR V8 produces more torque than power, but in an SD1 theres more power than torque, so even tho there the same engine what differences are there in the air and fueling????? ...... oh please dont say its cuz of the shorter inlet trumpets and shorter exhaust manifold system i already no that, this will only increase BHP by abit, but mainly helps with the air flow...... mainly i want to know what does the ECU tell all the electrical components to do differently from each engine, like how long each pulse width is, wot fuel pressure do they use cuz its all got to be different....... also works the same on my 3.9 and a TVR
anyone understand my question abit better and can help me understand abit more?????
oh by the way dan it didnt go close to 6000 RPM it was spluttering at 4300 RPM got home that day and found out it was a bit of damp in the dizzy. wipped it out and hey presto boy racer killer again and sounding even better 8)
i know ur a stubern arse but put it this way dan, its got enough torque at low end RPM to break 2 long half shafts, and a brand new diff, plus im sure its nakered my front diff aswell, but its still going :o
wont be at silverdale its off the road while i get an MOT
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