ihatepoundland Posted February 22, 2009 Share Posted February 22, 2009 This is something I've wondered about for a while, I've noticed that a lot of people, when referring to their tractor's power output always talk about H.P but very rarely mention torque. Why is this? Quote Link to comment Share on other sites More sharing options...
Lord Ferguson Posted February 22, 2009 Share Posted February 22, 2009 Generally speaking... the two follow suit pretty much (relative to engine cylinder (numbers of) and configuration (straight or V etc.) .. it's pretty much the measurement we use over here in Blighty really... But you are quite right in asking.... I always think of HP as revs and Torque as pure 'grunt' - you'd expect the latter to be the 'measure' of a powerful tractor really \ Quote Link to comment Share on other sites More sharing options...
NIGEL FORD Posted February 22, 2009 Share Posted February 22, 2009 whooooooaaaaaaahhhhhhh, ' dunno about that young Marky.. ...the 4 cylinder Honda 750 motorbike from the late 60s was the same power as the FORD 5000 (67 bhp) but nothing like the torque.... ' twood be interesting to see the bike trying to pull a 3 furrow reversible!!! Quote Link to comment Share on other sites More sharing options...
Lord Ferguson Posted February 22, 2009 Share Posted February 22, 2009 That's a good example of what I mean Uncle Nige... Motorbike... Lots of revs.. high HP... very little torque... Tracca (EVEN a Ford)... low revs... plenty of lugging power (torque)... \ Quote Link to comment Share on other sites More sharing options...
unkelfergus Posted February 22, 2009 Share Posted February 22, 2009 Ooooooohhhhhhh....................,nasty man!!!!! Quote Link to comment Share on other sites More sharing options...
marshman Posted February 22, 2009 Share Posted February 22, 2009 Umm. Diffent engines have peek tourque at diffent revs dending on what set up etc. Like high reving race engines have loads of hp but very little torque at lower revs. Diesals have lots of torqure at lower revs. I THINK You could have 1000hp race engine but it in a tractor and it would be usless i would guess? Knowing me im wrong? :D Quote Link to comment Share on other sites More sharing options...
ihatepoundland Posted February 22, 2009 Author Share Posted February 22, 2009 Generally bigger, heavier engines have more leverage and therefore more torque and inertia. What I find odd though, you could have take two 155(engine)hp turbo'd inline 6 tractors but one would produce 522 lb-ft (8.1l), the other 644.6 lb-ft (6.7l). Quite a difference if you only go by horsepower. Quote Link to comment Share on other sites More sharing options...
TM190 Posted February 22, 2009 Share Posted February 22, 2009 High speed, low torque. Low speed, high torque ;) Quote Link to comment Share on other sites More sharing options...
nick a Posted February 22, 2009 Share Posted February 22, 2009 Generally bigger, heavier engines have more leverage and therefore more torque and inertia. What I find odd though, you could have take two 155(engine)hp turbo'd inline 6 tractors but one would produce 522 lb-ft (8.1l), the other 644.6 lb-ft (6.7l). Quite a difference if you only go by horsepower. the motorbike and tractor comparison should give you the answers you need. take the motorbike engine its cubic capacity is smaller than the tractors, its piston area smaller/ shorter stroke to make this engine produce its power it has to rev hard. its torque curve is very small and has to be kept spinning for maximum output obviusly gained by the bikes gearing high output + high revs. something light like a motorcycle crankshaft at high revolutions doesnt provide masses of torque.A tractor engine obviously has a greater cubic capacity and heavier components driven by its four stroke cycle iumagine the force generated at the crankshaft/flywheel at each firing stroke of every piston. obviously a small cubic capacity 3 cylinder tractor engine with lighter components will not generate masses of torque, a four cylinder turb charged engine creates its torque through turbo boost pressure effectively increasing the engines cubic capacity providing the turbocharger is kept spinning to provide that boost as soon as the engine load is dragged down to a certain point the turbocharger loses its effectiveness and the engine dies. this is remedied in modern tractors with splitters and powershift stages. it took a good tractor driver to keep earlier turbocharged tractors working to maximum capacity under load. A big cylinder engine has big capacity,heavier components often longer stroke than fours and lower r.p.m.s and will often slog down harder, all turbo charged/intercooled engines have optimum range giving max H.P./Torque. tractor manufacturers often use different capacity engines to provide a range of horsepowers and torque characteristics. Massey Ferguson for example 165 used 207 cu.in engine then later 212 cu.in engine different horsepower/different torque another example mf 168 used 236 cu in and mf 188 used 248 cu.in engine. the cubic in capacity,weight of components,stroke length and governed speed all important elements in engine performance. Quote Link to comment Share on other sites More sharing options...
ihatepoundland Posted February 22, 2009 Author Share Posted February 22, 2009 Thanks, very interesting, you obviously know your stuff, there is a few things there I hadn't considered. The crux of the original question though was why mention of torque is far outweighed by people talking about H.P outputs when torque might be the more useful figure, is it just that horsepower is easier relate to? Quote Link to comment Share on other sites More sharing options...
nick a Posted February 22, 2009 Share Posted February 22, 2009 Thanks, very interesting, you obviously know your stuff, there is a few things there I hadn't considered. The crux of the original question though was why mention of torque is far outweighed by people talking about H.P outputs when torque might be the more useful figure, is it just that horsepower is easier relate to? i guess horsepower has always been the accepted way of expressing engine output, the original meaning of horsepower was the amount of work a horse could achieve within one working hour. if you look at tractor brochures now in particular the engine output is expressed in many terminologys. the most effective true rating of horsepower has always been the D.I.N. rating this rating gives true rating after frictional losses in engine and with all ancilliarys on the engine eg water pump,alternators etc the engine as installed. all tractors have frictional losses and power losse through to the pto, some more than others. pto rated horsepower is usually rated on the best torque curve, nowadays engines can be fuelled on pto work to provide extra horsepower. manufacturers these days with common rail technology do not have to have a wide range of cubic capacity engines to create a range of horsepowers and torque figures. most manufacturers have only one or two different cubic capacity engines and tailor output through engine management and fuelling. making the same engine perform differently and at different horsepowers and torques. manufacturers provide all this on there spec sheets, so when people ask which is a good tractor and which is a bad tractor when you understand the horsepower/torque you can get an idea. of course many many factors are condidered good/bad tractor manufacturers even often give fuel consumptions in dyno conditions although obviously tractor engine loads vary greatly. Quote Link to comment Share on other sites More sharing options...
nick a Posted February 22, 2009 Share Posted February 22, 2009 i guess horsepower has always been the accepted way of expressing engine output, the original meaning of horsepower was the amount of work a horse could achieve within one working hour. if you look at tractor brochures now in particular the engine output is expressed in many terminologys. the most effective true rating of horsepower has always been the D.I.N. rating this rating gives true rating after frictional losses in engine and with all ancilliarys on the engine eg water pump,alternators etc the engine as installed. all tractors have frictional losses and power losse through to the pto, some more than others. pto rated horsepower is usually rated on the best torque curve, nowadays engines can be fuelled on pto work to provide extra horsepower. manufacturers these days with common rail technology do not have to have a wide range of cubic capacity engines to create a range of horsepowers and torque figures. most manufacturers have only one or two different cubic capacity engines and tailor output through engine management and fuelling. making the same engine perform differently and at different horsepowers and torques. manufacturers provide all this on there spec sheets, so when people ask which is a good tractor and which is a bad tractor when you understand the horsepower/torque you can get an idea. of course many many factors are condidered good/bad tractor manufacturers even often give fuel consumptions in dyno conditions although obviously tractor engine loads vary greatly. take a diesel super stock tractor pulling engine that leaves the factory say for instance with a cubic capacity of 236cu .in rated a 75 horsepower governed speed 2200rpm. you then add two stage turbo charging to that engine with intercooling you get increased dense forced increase in cubic capacity. throw in lots more fuel and increase the revs you get around 1500 horsepower out of the same block. thats exactly what the massey lads tractor pulling team did with a massey ferguson 265 the most successful smallest capacity diesel engine tractor puller. Quote Link to comment Share on other sites More sharing options...
NIGEL FORD Posted February 22, 2009 Share Posted February 22, 2009 Marky.... you wouldn't want me to cite the FORD 4000 engine producing more torque from 3 cylinders than the MF 165 does from 4 would you....would you..... eh !!!... eh!!! no I thought not :D Quote Link to comment Share on other sites More sharing options...
nick a Posted February 22, 2009 Share Posted February 22, 2009 Marky.... you wouldn't want me to cite the FORD 4000 engine producing more torque from 3 cylinders than the MF 165 does from 4 would you....would you..... eh !!!... eh!!! no I thought not :D spot on nige greater cubic capacity Quote Link to comment Share on other sites More sharing options...
nick a Posted February 22, 2009 Share Posted February 22, 2009 spot on nige greater cubic capacity if any of you fancy having a go at tickling your tractors fuel injection pump to increase horsepower remember this only works to certain degree then you end up over fuelling them getting lots of black smoke/unburnt fuel. the fun old saying no poke without black smoke the engine for its cubic capacity is producing its maximum and aswell as drinking the fuel its wasting it. some makes were just more fuel efficient than others before these emission regulations came in, and we all know which they are. before the ford bashers jump up and down with glee dont tar all fords with same brush!. the three cylinders never smoked or the bigger 401 cu.in six cylinders, the fours smoked more often why ? fords were pumping in the maximum fuel to get maximum power output. mf used to be the same with perkins engines admittedly not quite to the same degree. it shows how much design has moved on. why you get that big black cloud when you open her up - wasted unburnt excessive fuel. Quote Link to comment Share on other sites More sharing options...
Light Land Posted February 22, 2009 Share Posted February 22, 2009 Marky.... you wouldn't want me to cite the FORD 4000 engine producing more torque from 3 cylinders than the MF 165 does from 4 would you....would you..... eh !!!... eh!!! no I thought not :D You ford lads are all torque... Quote Link to comment Share on other sites More sharing options...
nick a Posted February 22, 2009 Share Posted February 22, 2009 You ford lads are all torque... not just ford mate! i have been involved in v8 stock car racing too with chevy 350 cu.in v8 engines. the rules state original block no re-bores or skimming to increase cu.in,standard rods & pistons. we altered engine output and torques through r.p.ms,fuelling and timing . we could advance timing, alter fuelling and revs on rolling road dyno. make a note of all settings so we could change the engine tuning for different tracks if you want more power for acceleration or top end grunt down the straights. come scrutineering even if they call for engine strip hey presto all legal and above board. those who knowledge and access to rolling road dyno and timing gun at an advantage. the other way of tuning horsepower to the track is changing gearbox ratios to suit each track with a nash racing gearbox. bit similar to a power harrow gearbox you can quickly change the gears around. Quote Link to comment Share on other sites More sharing options...
NIGEL FORD Posted February 23, 2009 Share Posted February 23, 2009 spot on nige greater cubic capacity I seem to remember the 4000 was/is less capacity from my comparisons yonks ago, but I know some people put the 4000's greater torque down to a bigger flywheel. Quote Link to comment Share on other sites More sharing options...
nick a Posted February 23, 2009 Share Posted February 23, 2009 I seem to remember the 4000 was/is less capacity from my comparisons yonks ago, but I know some people put the 4000's greater torque down to a bigger flywheel. yep you probably right on cubic capacity and flywheel i havent checked data/specifications, did ford 4000 engine have greater r.p.ms aswell- they certainly were lively performers. ford tractors and conversions with ford 2700 series 6 cylinder enines certainly could be smokers and very thirsty. on the subject of cubic capacity IH 674 engine was close to the capacity of a ford 7000 andcould be fitted with the same turbo, but due to valving/porting etc could not achieve seem gross horsepower but could provide good boost in p.t.o horsepower. Quote Link to comment Share on other sites More sharing options...
nick a Posted February 23, 2009 Share Posted February 23, 2009 yep you probably right on cubic capacity and flywheel i havent checked data/specifications, did ford 4000 engine have greater r.p.ms aswell- they certainly were lively performers. ford tractors and conversions with ford 2700 series 6 cylinder enines certainly could be smokers and very thirsty. on the subject of cubic capacity IH 674 engine was close to the capacity of a ford 7000 andcould be fitted with the same turbo, but due to valving/porting etc could not achieve seem gross horsepower but could provide good boost in p.t.o horsepower. i have pictures somewhere in the depths of beyond of a ford 4000 select o speed that use to drive a claas 60 jaguar and tow load in fairness it did only operate on flat ground. Quote Link to comment Share on other sites More sharing options...
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