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Which is better.. Torque or BHP





aha, this old chestnut.. the one that most people seem to struggle with.

in Surfer dood terms.. heres what happens and what it means.. as Davina would say.. then YOU decide...

I will use my beer bottle analogy lol..

let us consider torque to start with..

there is a guy, called Fred, who applies for a job at the local ale house.. he refills the bottle shelves when empty.

Now... how many bottles can Fred lift in one go ??. - basically depends on how strong he is yep ?..

So, - Fred, cos he works out.. can lift 48 bottles in one go.

his maximum lifting capacity we can call his torque.

this is all well and good.. but to know if Fred is the right man for the job, we need to know how much work he can do... this work, we will call BHP (Bottles he processes lol)

All Fred has shown us so far is that he can lift 2 crates (48 bottles) in one go.

but, we want him to move those bottles from the celler to the bar.

we time him, and it takes him 30 seconds to carry the 48 bottles to the bar.. so, we can work out roughly how many bottles per hour he can move yep ?.
If we try to increase the number of bottles he carries, he may stagger and slow down, maybe taking 35 seconds to get to the bar.

His work output (BHP) is therefore based on the number of bottles he can carry in one go.. and the time it takes to do the trip to the bar.

Bill comes along to the interview.. this time, Bill is not as well built as Fred.. he can only physically lift 1 crate at a time (24 bottles).. his torque is lower.. but it is meaningless unless we know how fast he can get to the bar.. because Bill is built like a racing snake.. he whips the 1 crate to the bar in 14 seconds..

His work output is his torque (Amount he can lift) times the number of trips he can accomplish, in say an hour.. times the number of bottles.

if the return to celler time is the same for both guys.. it is actually Bill who moves more bottles and hence does more work in a given time period.

Now Jim comes along.. Jim is built like a brick outhouse... he can lift 4 crates no problemo.. he jogs to the bar in 17 seconds.... who does more work now ??

The wieght of the bottles is the key here, not the physical size of them.. the end result is a weight moved over time..

the meaning of all this.. ???

there is no difinitive answer for which is better .. it is a matter of knowing the weight to move and the time it takes..

now find something to fit the profile.

Joe.
 


talkin about boots, have any of you seen a megane classics boot!!! its huge, biger than any vectra or similar...may be bigger than the laguna!!

p.s., ive been trying to talk about torque for a long time, but sometimes my explanations arent as surfer as yours. and besides!!! i am a surfer!!
what did it for me was an article in performance bikes by ummm....the technical editor from performance bikes...john.
hes passed on now, cancer....genius, what a waste.
 
  mk2 172


my cars man came from the circus and can juggle 6 crates to the cellar whilst on a unicycle in 5 seconds
 
  Scirocco GT TSi DSG


"because Bill is built like a racing snake" Who in their right mind would race smakes?

Plus Bill has no arms (see above quote) so cant lift anything.

The answer is they dont need to employ any of them as they have done all of the work during the interview stage, all of the bottles have been moved.

Alright, I think BHP is the most important factor, but this is a totaly uneducated opinion.
 


Hi Greeper..

but.. WHERE is that bhp produced.. ?.. at WHAT RPM .. ?

What is the torque curve like at that point..

are your gearbox ratios suitable.. ?

BHP IS an important factor.. along with the torque.. so is the steepness of the bhp curve..

All good fun huh ??..




Joe
 
  2005 Audi A3 3.2 Quattro


So which would be better in a race?

Man 1 who can lift 48 bottles and get them to the bar in 30 seconds?

or

Man 2 who can list 24 bottles but get them to the bar in 15 seconds?

Would this be similar to say a 4 litre, 2 ton car taking on a 2 litre, 1 ton car? (given they both have the same BHP and Torque per ton)
 
  Scirocco GT TSi DSG


Has the weight of the actual men got anything to do with it, e.g the amount of energy each man uses to do the same job?
 
  VW Transporter 174


Surprised this thread didnt go further!

Anyway, ive raced three chipped FRSTs since i got my motah and although they may pull slightly when the turbo first kicks in i always hang onto their coat tails and when the turbos done its best i slay em
so heres my theory.........
does chipping generaly only increase torque?as chipping(increasing boost) has little effect on top end power as HP is controled by the flow capacity of the cylinder head,does this make sense?
its just that when ive been on dyno days with turbo RSs they sometimes give figuars of what bhp a car would give if it could HOLD the boost.

So to put it in slarty speak,FRST lift a lot of bottles at once but their work rate (bhp) controled by its flow capacity is less than a 172 clio

172 Slayer
 


Hiya Slayer m8 !

re your theory.

chipping a forced induction car can increase both torque and bhp..

due to the equation, (BHP=Torque * rpm) / 5250, as the torque increase, so does the bhp.

the interesting part is where the bhp is rising rapidly, but the torque os decreasing - as seen on most plots.. ie - the rate of change in bhp, if calculated with torque decreasing, is still producing a rate of change that allows a greater rate of acceleration depending on the weight of the car - thi s is where the rapid acceleration can appear from..

accelleration of an engine obviously depends on the load applied, but, there is also a finite limit that the engine internals can be accelerated, this is often a governing factor in early stages of a run.

BHP, is certainly relative to the flow of the airpump.. in a N/A unit, on a turbo unit, with good head design, the flow is forced and can overcome most limitations of poor flow design.

torque will overcome the weight of the vehicle and losses, but you need a steep bhp curve at useful torque to produce the goodies..

in slarty speak you are almost correct.. the rst DOES lift lotsa bottles at one go... but its rate of work is less than a 172, not only due to its max potential flow capacity directly (VE), but due to its poor engine design...

Items such as valve train design and weight pay a MAJOR part, rotating assemblies such as crank shaft rods and flywheel have also to be accelerated..


you can make an rst bottom end as good as 172 in terms of dynamic balance and weight, but you cant get the top end anywhere near. The F4R (as used in the 172) is the closest to F1 technology I have seen, hollow, lightweight cams, roller rockers, miniature cam followers, lightened pullies, superb head design etc.... will piss all over an rst..

the potentials for the turbo clio 172 are tremendous..

the key to accleration is weight.. less off...

torque.. more off... see note 1

BHP ... More of .. see note 1

note 1. torque without an appropriate rate of change capability (BHP) is meaningless for accelleration...
BHP without enough torque will be bogged down by vehicle weight.
the best combination of rate of change *BHP) in a climbing or static torque curve, or, a faling torque curve where bhp is rising faster, (percentage wise), will always give the better performance.

that really is the answer to life, the universe, and everything

it took me many, many years of head scratching to work that simple fact out..but when I understtod it, everything else became much clearer in the field of tuning and performance.

Joe
 
  BMW 320d Sport


Well IMHO all this torque of which is better torque or power comes about through motors that have a decent amount of one and not much of the other, diesels in general plenty of torque but not a lot of power, and petrols the other way round.

Best way to have a fast car is get something that has plenty of both, that way you wont get beat! Luckily I have both so no worries mate.
 


But, Nick....

put yer teachin head on for a mo dood


yes, you GOTTA have lots of both.. but the RATIO WILL dictate your results.

get that sorted, and you KNOW where to gain performance, and not lose it, as soooooooooo many do...


Joe...
 
  VW Transporter 174


Another superb post there Captain!

have you thought about moving over to the "other side"
we have got T16s Ks KV6s to play with!!

Slayer
 
  BMW 320d Sport


hehe yeah if you wanna get technical Joe I know where youre coming from. But my point is that a lot of people think forced induction is the ultimate route to power or torque or whatever. When really there is no substitute for raw capacity...which gives you both power and torque.

Ill take the NA V6 in the Clio over a 2.0 turbo in a scooby any day. Then get busy on the engine and see some real power.
 


Taken from the VW website

Torque is a force that tends to rotate or turn things, and in a car it can be used as a measure of the responsiveness of acceleration. Measured in lbs per foot, the higher the torque the more responsive (and faster) the acceleration.

In laymans terms, torque provides the car with oomph.

A good example of torque is when you tighten the wheel nuts after changing a tyre. You create torque with the spanner by applying force to the handle, which creates a torque on the wheel nut.

Similarly, the cylinders in a car engine create torque, and use it to spin the crankshaft. The more torque an engine can create, the more usable power you have in the car. So on the road, higher torque will make overtaking easier, provide better low-rev response and give you greater flexibility across the gears.
 


BHP or torque or talk!
Lots of people on here talk about beating ERSTs but they havent got 2 litre engines, Cosworths on the other hand have, dont seem to hear many stories of you guys racing them.
Now I know u guys aint got turbos, but that is the way your engine have been desined. To fit a turbo would involve sh!t loads of work, including pistons to lower your compression straight away, cams, timing would need retarding, bigger injectors etc etc.
Now I also read the RSOC B/B and I can garauntee there are plenty of ERSTs on there that are way quick even with there ancient designs.
Your cars are state of the art modern designs and damn quick for what they are, but it is a damn site easier to tune a ERST/Cosworth to silly power levels, I honestly believe that your cars havent got much scope for sensible tuning.
Obviously youll be able to see what car I drive, and havent just come on here to sl@g your cars off, but anytime I read this board all I hear is I beat this and I beat that, or I stayed with this and that, it just sounds like you have an inferiority complex about your cars. They are a nice car. Handle well, brake well, go well, for what they are, but when you talk about Cosworths u would be lucky to find a standard one to race, cause its so easy to make them stupidly fast wether due to BHP or torque. For £400 my mechanic could give a cossie 330 Hp with torque to match. Also not bad for a 15yr old car!
PS My car is in another league so I dont want a lot of offers to a race, maybe just go easy on the old ERST a guys.
 


"but anytime I read this board all I hear is I beat this and I beat that, or I stayed with this and that, it just sounds like you have an inferiority complex about your cars."

How come people posting there storys automatically means they have a inferiority complex?. I think sometimes it makes entertaining reading, if you dont like it dont read it. Ive come to the conclusion that some of the guys just want to share some of the fun they have had on the road , thats one of the points of driving a sporty car to have fun against other cars I think it is not a safe thing to do. Do you think we give a sh*t that your cars is in a different league?, theres always a faster car out there no matter what you have I dont think anyone here seriously thinks that a normal clio would keep up with a modded cossie. If I wanted a cossie I would of bought a cossie I and a lot of people here know that the RST/cossie engines are very easy to tune but what Capt is saying is how old and pants the RS turbo engine design is compared to the newer (but less tuning capability) engine. There are currently around 4 of us going for turbo clio 172s. Inlet, exhaust manifolds , turbos, injectors are from and developed by renault themselves for the F4R (I think thats the engine code) engine, whats needed now is lower compression pistons, and a ECU to map it all. Yes it does involve a lot of work but the outcome is a rather nippy clio. Im personally only going for around 250Bhp I dont really know what the other guys are going for. From Capts exploration of the 172 engine it has come to light that the engine was designed for a turbo in mind, the crank was designed for some serious power. I raced against a cossie the other day. I think it was standard , after a few runs lots of black smoke came out of his exhaust When he pulled of we smiled and waved at each other , a bit of fun.

Chun.
 
  BMW 320d Sport


Hang on, whos caning the ERST on here? I dont for one. I might cane them on the road but not in writing! The argument that its not a 2.0 is a non-starter, the whole point of a turbo is that when youre on boost the pressure gives you effectively a bigger capacity engine, I dont know all the figures cos Im not a turbo-head, but Im thinking along the lines of a bar of boost pretty much doubling your cars capacity. So a 1.4 R5GTT is effectively running a 2.8 on a bar of boost. OK its not that efficient so lets say that on (1 bar) boost a standard GTT would be equivalent to say a 2.0-2.5 litre lump.

You say we havent got turbos because thats the way the engines designed. More like turbo cars engines arent designed properly and only actually work well when theyre on boost, before that theyre gutless when you compare their raw capacity with other cars of the same engine size.

Anyway, the point is that every forum is full of kill stories, thats just the way people are. I aint seen any Cossie drivers claiming they caned a Noble M12, I wonder why? And does that make Cossie owners a load of pussies with sh1t cars? No of course not. So why do you show that attitude about Clios?

Apart from anything else, Im not afraid to challenge a Cossie anytime, anywhere. I might not beat the majority of them ( as you rightly say, most arent standard and turbo tuning is a piece of cake compared to NA), but Ive caned a few on the roads and if you ever had a passenger ride in my little Clio I think it would open your eyes. Plenty of times Ive come up behind Cossies and they dont wanna play; maybe they reckon theyre so superior to everything else out there that they dont need to bother. Or thats what they tell themselves anyway when I pull past. Im glad the Scoobies turned up when they did, it was about time someone challenged the Cossies properly.

Not wanting to diss Cossie owners but plenty of times at shows, 1/4 miling, cruises etc Ive seen Cossie owners all together, I ask them stuff about their cars and they shuffle their feet and act like theyre bored and they dont need to fraternise with anyone else. Thats just my experience and I can assure you it doesnt happen when you chat to Scooby owners.

Anyway I rate the Cossie, everyone does, but IMHO its had its day and the shape is like some 80s throwback. Thats just me, I wouldnt want one, except an ESCORT COSSIE which I would love cos that has a bucketload of style as well as raw power. But its your PS that cracks me up, you talk all the talk and then tell us youre in a different league! Its not us thats got an inferiority complex, its you with a *superiority* complex!
 
  Scirocco GT TSi DSG


I agree with Nick 100%, my cousin has an Escort Cosworth, chiped etc can do 175mph etc but also looks like it can. Guy near me has a Sierra Cosworth 4x4 with bright yellow wing mirrors and bumpers, looks sh!t, sorry Sierras look very old these days.

Why would anyone want to race a Sierra? They are ugly, and dangerous, they may be capable of incredible speeds but can the rust filled bodies cope? Probably not! They are not a scalp people want, sorry.

Clios may not be as fast, but they handle better, they look better and as you say are in a different league.
 


Getting bacto the original conversation, I can give an example that is easy to see.

My old 1.6 8v Nova was running on Weber 40s with small chokes. It had stupid amounts of torque, but on the rollers, the Horse power was down around 140bhp. On the 1/4 mile, this would give really quick initial acceleration, possibly below 6 seconds to 60mph, but when I started picking up speed, the rate of acceleration slowed and my top speed was limited. The Nova I drive now is a 1.4 16v with 185bhp, but very low torque. The initial acceleration is poor probably around 7.5 to 60 as it normally bogs down (lack of torque), but once the revs build, its seriously quick and covers the 1/4 mile in a similar time to my old Nova, just with a quicker terminal speed.

I had a couple of head to heads with 172s in my old Nova, and every time without fail Id wipe the floor with them to 60mph, hold on till about 100, then see em leave me behind.

Now the conclusions I draw from this are: If I want a car that is quick to 60mph, Ill choose large low down torque. If I want a car that is quick on a race track, where the revs never drop, Ill pick BHP, but obviously, you cant have one without the other, so there is always a balance to find.

So out of interest Joe, what would be the ideal?;

Gaining peak torque low down, and holding it until max rpm? Or getting a steep initial torque curve, that never stops climbing? Or....

MC

Oh, forgot to say, gear ratios are vital.

MC
 


I swear weve had this conversation before Ben, I typed a spec for you. yes it did cost alot, and know I didnt pay for it. I get to drive it, but alas I dont own it.
 


oh....just remind me abit..please.

but that below 6 secs to 60 fomr teh 1.6.......i cant quite get my head round it!
 


We went on to talk about driveability and power not coming on till high RPMs. You were saying about the go-karts (I think) that you used to race that you would stall and flood with petrol of you let the revs drop too low? Anyway, the 1400 was originally an 8 valve Nova block (kept that way for a reason) with the corsa head. Intruder pistons, TBs DTA management, Sodium filled valves, de-seemed shot peened rods, goes on forever.

My 8 valve 1.6 was bored to around 1650cc with raised compression. The head was done by Blydenstein using 2mm larger inlet valves and 1mm exhaust, the cam was only a fast road job (one of the contributing factors to the power distribution) the inlet ports were taken out even further and the inlet manifold matched as a one off. The exhaust manifold was a 4-2-1 with primary pipes about 32". I used a mix and match of gearboxes to get the ratios as close as possible. 4.18 fd, and the close ratios from an F10CR. The car was stripped bear of anything I didnt need, basically had two buckets a steering wheel, clocks and gearknob. Anyway, the key point was the 30mm chokes I was using. They are really too small for that engine. I had friends with much higher BHPs around 160, but using 34mm chokes. My horse power was well down. At rolling road days it was almost embarrasing as the car promised so much, but without demonstrating on the road you couldnt appreciate it. The torque was so severe that I eat through tyres in no time, and would wheel spin in 4th and possibly even 5th in the wet if the road surface wasnt good. I really needed to invest more, but broke it for parts to pay for marriage and honeymoon.
 
  BMW 320d Sport


MC some nice ideas on 0-60/1/4 mile there. Ill give that some thought...mine always seems to come out crap on bhp (on the rollers) but torque is always good.
 


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