you hear people saying i have a 450 bhp cossie etc

how do you increase torque like race cars to a stupid amount and woudlent it be more worth while to do that instead of chasing bhp figures.

if its unclear some one said on here bhp sells cars torqu wins races. if you why dont modders increase the torqu of there cars greatly surly this would be more benifical

im a little confused haha

 

imo bhp is the key, take the monaro its a prime example pulls well in all gears but its lazy uuumph, whereas tuned high reving bhp pulls harder and harder to a high rev limit. at the end of the day you cant have one without the other at any given rev point so there both as important as each other i suppose.

 

Who ever said that should put the crack pipe down.

Torque makes a car feel fast

BHP makes a car fast.

Look at F1 cars.

 

Carol shelby said it & i think he may know rather more about performance cars than you .
Dont start to compare F1 cars limit them to a 7k rev limit & then see how they perform .
Huge flat Torque curve is what makes a fast road car you only hit peak Power once in every gear. Big Power will however push up your Topspeed.

 

aaaargh!

Carol Shelby had a point, he just didnt sufficiently idiot proof his comment.

Peak torque is irelevant
Peak power is also irelevant, unless youre in a race car with a million gears so youre only ever at that particular rpm.

What matters is the area under the power curve!

 

isn't torque the power of pull and bhp the speed of the pull thats how i'v always seen it anyway, and like said you usually get one with the other, just like voltage volts is speed of the current and amps is the power it has.

 

my old cos was 368 bhp per ton and i did 30 - 130 in 14 seconds, skyline is 391 bhp per ton and did 30 - 130 mph in 10 seconds those readings arent dead accurate like timing gear but they are accurate to each other for comparison, now the skyline has more power and torque for longer in the rev range but which one is giving the most gains i have to say both as there both relevant to each other at each rpm, we cant defy the laws of physics

f1 cars are proof that torque isnt needed but who has £10000000 for an engine realistically the decifering factor is the size of your wallet

 

to be fast on the road in gear in need high torque a 600bhp car with say 380lb ft would not be as fast as a 500bhp car with 500lb ft of torque on the move!

 

Motorbikes

Fuck all torque........but loads of revs........as rpm goes up VE goes down but power keeps rising

If you can make high rpm, torque is less relevant as long as gearing is right

 

fi cars are flat out at a high rev limit were bhp counts rally cars which are caped to 360ish bhp are proof that torque makes u fast low down and in gear as they have massive torque and they are very fast low down and in gear!

 

and also weigh about 250kgs so hardley a good example as they dont need high torque to be fast!

 

if in the same gear at the same revs then yes 500 / 500 would pull harder, but it doesnt happen like that 500 / 500 will pull harder early in gear but 600 / 380 will pull harder later in gear. a bigger spread of more power / torque is the winner.

 

good example would be focus ST and CTR then

focus ST (225bhp and 239 lb-ft) 0-200 km/h 27.6 seconds
CTR - (197bhp and 145 lb-ft ) 0-200 km/h 27.9 seconds

 

I wouldent agree with that mate bhp is top end power most race,s on the road happen in gear. In gear power on the move is wear torque comes into play high torque is the winner if your talking about meeting in gear at the same speed

 

drop a cog, floor it and you will always be 5k revs up, gears gears gears my friend i understand what your saying but when im out on a spirited drive im not poodling about in 5th gear im in the revs all time its there ready to go. but in a controlled environment where both partys have to start at a specific rev , gear , speed then yes torque will win but so will bhp as you cant have more of one but not the other at any given rpm

 

are they the same weight ? or is the st very peaky ?

 

yeah but if u meet at 60 what ever gear your in with more torque u will pull harder!. If your driveing along at 50 on whatever road and u see some one come up behaind u and think ill race that as u do lol drop a gear or not with more torque u will accelerate harder with the power example i said in the earlyer post

 

ok example of 2 cars ive owned both cossies old stage 3 that had more torque but less bhp than my white saph, stage 3 was alive quicker and pulling hard but once your on the move and in the revs the white saph would fuck off into the horizon. when the stage 3 is running out of puff the white saph is screaming into high revs, but the stage 3 has more torque but less bhp and loosing. with a small peaky power band the usable power gets more as the gears get bigger as you can keep higher up the rev range. either way one thing is for certain one is just as important as the other, they go hand in hand

 

i think in some of these posts wind resistance and drag have to be taken into account too, as well as power to weight as scooby slayer has already mentioned, as these make a big difference, doesn't rod say that if his engine was in a different car with better aerodynamics then he'd see a higher top speed and iirc thats why martin built his mk1 mondeo cosworth as it's aerodynamics are better than the sierra so was hoping to see a better top speed from a smaller powered engine

 

The only thing that matters is torque@the wheels, torque anywhere else is meaningless, and torque at the wheels is related directly to BHP @ flywheel, but not related directly to Torque @ Flywheel (you need to know rpm too in order to determine gearing, and then its BHP you are looking at anyway)

Carol shellby was talking about low down torque to hook up a nearly limitless traction racecar, fuck all to do with what happens once you are moving and totally irrelevant to any other form of racing, where BHP is what matters

 

ay! i feel like i'v just read a circle , just a question but how is torque at the fly not related to the wheel as surley it's passed through the transmission, genuine question as i'v just been boggled by your reply

 

Torque @ fly without an RPM reference is meaningless.

If you have 500lbft at 1000rpm and then it tails off, your sierra weight car will be fucking slow.
If you have 500lbft @ 5000rpm, the same car will be very fast.


Its totally meaningless to talk about a lbft figure without an RPM reference as well, it could mean a lot of power or a little.

So what you need to really know if your engine is going to make your car fast or not, is to know the product of torque and rpm, and guess what the BHP figure does? exactly that!

 

ah ok i get the picture cheer's, so i guess some of it is to do with the rotational force that comes with rpm, have i got that right as i'v had a long day thats not helping me get my head round the equasion as easy.

or is it to do with the split between engine speed and transmission speed as all that power at 1000rpm would mean no use to the gearbox to pull you along but a build up of the same torque to 5000rpm would allow for more acceleration meaning quicker build up of speed as gears get longer higher up the rev range.

if i'm completely off the mark i'll just wait till tmoz when i can get my head round your reply's better.

 

Think of it like this:
Torque is how hard you push
RPM is how many times in a minute you push

Pushing fairly hard lots and lots of times will move the car faster than pushing very hard once.

BHP is a figure that combines both to show which one will result the most work done.
Hence why BHP is so relevent.

 

lamens terms worked.

but it's as my first reply on this thread suggested then, a bit like electrical current in theory i.e voltage combined with ampage, admitted i never knew bhp was a combined equasion of torque vs rpm, so like you say bhp is a more relevant figure for actual speed

 

actually come to think of it i'm sure i got taught this in physics as it's ringing a bell, i'v just not used it for so long.

 

Yes its exactly like Volts alone is meaningless in seeing the real power of an electrical current, as is amps alone, you need both to know what sort of force you are dealing with.
Exactly the same for torque and rpm

 

cheer's chip i got there in the end , i do remember doing this in physics now i remember there was an equasion to figure out hp using torque/force+rpm but like i'v said it's been so long since i'v used any of it i'v forgotten it all.

 

bhp = ( lbft * rpm ) /5252

 

Which barring the shitty imperial conversion factor is like P=I*V for obvious reasons.

The motorbike example for inatance...

if a car makes 171bhp and 150ftlbs from a 2l n/a engine at 6000rpm and a bike makes 171bhp and 75ftlbs at 12000 rpm, by gearing the bike down by twice as much you will end up with the same wheel torque and rpm at that point.

The car engine will always be faster in a car however because youll find that at 4krpm the car engine makes 110ftlb where the bike will only make 48ftlbs at 8k or whatever. It might be the same at one single point, but lacks the "spread of torque"

 

You need enough spread to cover the width of your gearing but beyond that is just a luxury and not relevant to the potential for straight line acceleration.

So on my nova for example, I need power from 6k-8krpm, as thats what the revs do during gearchanges, anything below 6Krpm is only relevant to how it drives, not how quick it is in a straight line.

So yes you need some spread of torque, but its not vital you have lots of it from a performance point of view.

Obviously if you are doing something like road rallies where you will frequently find yourself in the "wrong" gear due to the nature of the terrain, then more spread then becomes key and is worth sacraficing top end to achieve.

 

well said mate. your replys have sort of said what i was trying to say. but your more knowledgable than me so can expain it much better and know what your talking about lol

 

Torque is useless without HP and vice versa. Torque is the "Pull" or grunt, that's why lots of low down torque like a V8 or diesel makes for good acceleration or "Pulling Power" unlike VTEC engines which are the complete opposite of this but gain more power from 6K upwards when the cams switch.

The volts and current is directly related and is how I think of it, like ohms law you can use the said calculation to figure the power.

I.E a static shock has many thousands of volts but not a lot of current equates to lots of power but not alot of torque in engine terms.

Martin

 

This subject has always confused me. Lets take diesel cars as an example, a diesel car with 112bhp per ton but over 300ftlb of torque can almost keep up with a car that has 155bhp per ton but only 150ftlb? Torque must count for something?

 

TBH try reading the rest of the thread.

 

as per chip ..... its power and gearing as i said

 

BHP is purely a measurment of how much torque is being delivered per cycle.

Power is Force x Revs. So, BHP is derived from how much torque you have. People harp on about Torque and Power but essentially they're the same. It just so happens, that turbocharged car engines deliver the most torque at a point relatively low in the rev range.

You make less torque high in the rev range, but as you are producing more revolutions you make more power.

Anyways. Carrol Shelby was right!

Torque does win races, because it's your torque that gives you your power. Simples.

 

No it isnt, not at all, not even vaguely, you mean per time period, not per cycle.



Yes that is correct

No its how much torque multiplied by how many revs, its meaningless to talk about just one element of the equation in terms of the resultant value

No they arent, power is torque multiplied by revs, so without quoting the revs too its in fact totally different.

Only if they have a small turbo, my nova makes peak torque at over 5000rpm, higher than a lot of N/A cars do.


Thats a pointless over simplification as without qualifying how much less torque you are making you cant possibly comment on if it will make more power or not, the only time you make more power higher in the rev range is if torque isnt falling off as quickly as revs are rising percentage wise.


In the context of hooking up an effectively unlimited grip drag car yes he was


Thats simply not true, its a combination of torque and rpm, and in fact in F1 its the rpm that the rules have limited in order to limit power being gained at the potential expense of reliability or increased dev costs recently just to prove how equally important it is.

 

To answer the original question.....increase torque by conventional methods i.e forced induction. Increasing the volumetric efficiency of an engine will bring a gain in some form or another. Assuming the engine application is for a road car, then an engine with longer stroke would be preferable.

 

my vw diesel has 553lbft of torque and 308bhp but it wouldn't keep up with a stage 3 saph