BHP and Torque

BandyQuill said:
the S isnt that much lower than the focus tbh, standard 240, with overboost its 260... and dont forget it weighs half as much :p

and lets be honest, its not boring like a focus ;)
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Mine's an "S", 176 BHP, the JCW is 212. It just doesn't pull like the ST, but then the ST can't go round corners like the "S", and 38mpg is much better than 22 :eek:
 
This may help to see the relationship between bhp/torque/revs.

This is a graph of my bike. As you can see peak power is at 10,750rpm and peak torque between 8000-1000rpm.

The thing which is important in my eyes is the bhp line, no dips or flat spots just good linear power.

Also there is a good spread of torque between 6000 and 11000 revs.

GSX-R1000K5Dyno.jpg
 
You can't beat a good car club 'rolling road' day out at a garage somewhere, "sigh thoses were the days"
 
Lol, you're so right, Its the beaming faces on the way home ...yeha!

Can you not ride anymore then? bummer if that's the case.

wookey said:
This may help to see the relationship between bhp/torque/revs.

This is a graph of my bike. As you can see peak power is at 10,750rpm and peak torque between 8000-1000rpm.

The thing which is important in my eyes is the bhp line, no dips or flat spots just good linear power.

Also there is a good spread of torque between 6000 and 11000 revs.
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Hmm nice curve Adam .... very smooth and smoother than most. :clap: Did it take much work to get it sorted like that?
 
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onomatopoeia said:
Newton's second law? I'm assuming non-relativstic velocities since we are talking cars.
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puggie said:
Without taking into account the gearing the torque is relatively meaningless. as said above if you have 2 engines one with 100lb.ft and one with 400lb.ft the 100lb.ft one could accelerate faster if the gearing is right for it!
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My hat is raised in respect for your politeness guys. :clap:

;)
 
Forbiddenbiker said:
Hmm nice curve Adam .... very smooth and smoother than most. :clap: Did it take much work to get it sorted like that?
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Thanks Adam, that was at first service with a Yoshi can, BMC Filter and PC fitted. Just a couple of hours on the dyno with one very clever chap :)

It's now making about 168bhp and 80ft.lbs with a few miles on it.
 
JohnStewart said:
Not an entirely accurate description, but it made me smile: "Understeer" is when you hit the fence with the front of the car. "Oversteer" is when you hit the fence with the rear of the car. "Horsepower" is how fast you hit the fence. "Torque" is how far you take the fence with you.
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Thanks for that mate, now my OH understands what the guys at Top Gear are on about :)

need to buy you a :beer:
 
Forbiddenbiker said:
Yeah they always get a little quicker after some miles have been clocked up ...Like an auto blue printing lol ... Tis very impressive work indeed Ad, well nice torque, wowzer! ... I bet it feels great.


Throw us a name if he’s that good could you? ... always nice to know who the good guys are.
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A few miles does make a big difference. The chap who mapped it was Alan Cook at Crescent Suzuki. He now has his own company R&R Performance with Mark Hanna ex Crescent Suzuki as well ;)

When I had it on the dyno last the guy who dyno'd it was a chap called Steve at GT's in Plymouth and he commented on how good it was, especially the fueling.

What bike have you got Ad?
 
Another graph for example:

dscn1300k.jpg


you can see how the peaks in torque match up with those in the power curve.
 
wookey said:
A few miles does make a big difference. The chap who mapped it was Alan Cook at Crescent Suzuki. He now has his own company R&R Performance with Mark Hanna ex Crescent Suzuki as well ;)

When I had it on the dyno last the guy who dyno'd it was a chap called Steve at GT's in Plymouth and he commented on how good it was, especially the fueling.

What bike have you got Ad?
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Ah right, some crescent guys, I’d imagine they know what’s what indeed. :D Ta for the details.


I have an Laverda 750cc Formula, mostly. ;) Newer type not old. Kind of an Italian love affair to be honest, its my fave commuter bike when the chance arises but it not easy to ride in that environment ..

Laverdaform.jpg


I did lots of mapping mods in its early years, it done 50,000 miles since then, Europe twice etc. I have piggyback roms from FIM (Australian company) the race chip is their greater bhp map that I’ve modified using real time data and gas logging to make more use of the ram air system… The piggyback above that chip is my re-mapped for London ‘lower throttle trigger points idea’ just to make the thing more usable around town… to be honest I was only semi successful at that second map, and I cant really use it day to day… but it was fun trying.

This is a chart of such a test run showing the ram air making its impact.
Tricky to read I know, just take my word for it.

The test route ran like this; Set accelerometers, pull off, curve in track to straight, chicane (25 secs in) , longer straight, chicane, straight, end of test (93 secs in), off throttle and a ‘u’ turn.

dynoCHART.jpg


The bhp and torque follow each other as you'd expect, but they are measured by accelerometers and the figures seen above are calculated afterwards, they also measure lean angle and gear changes so looking at the chart from a traditional dyno angle wont work.


On a good dense air day :D Im around 68ftlbs pound max (I its a long stroke twin) 98 bhp@9k at the rear wheel. 177kg un-fuelled….. and it seems to get more exciting the older I get.

If you’ve never ridden one do have a try of a formula, Bit old now but Its an exciting and engaging ride that demands you throw yourself into the taught arms of its Laverda racing pedigree.


Main thing though … Laverdas sound, better than one can imagine…
 
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our little nitro engines dont have masses of torque or BHP but we can pull around 40,000rpm :D

you can hear one scream in this vid http://vimeo.com/17009827


the onroad guys need less torque & more revs as their cars are lighter & faster & they pull over 50,000rpm nowadays :wacky:
 
JohnStewart said:
Not an entirely accurate description, but it made me smile: "Understeer" is when you hit the fence with the front of the car. "Oversteer" is when you hit the fence with the rear of the car. "Horsepower" is how fast you hit the fence. "Torque" is how far you take the fence with you.
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My favourite description! :D (y)
 
A good layman's explanation of torque is to think in terms of rowing a boat. Initially, starting from stationary you're applying enormous force with the oars pulling against the water, but as your speed increases, it becomes harder and harder to apply effective enough force toincrease speed.
 
Sorry Adam forgot about this thread!

Nice bike mate, looks like you've had a lot of fun with getting it usable! lol

How did the get the data on the test run?
 
Torque is pulling power bhp is just power. The best example I can give is this.

Two cars, same engine size and same bhp and also same weight. One diesel and one petrol. They have a race 1/4 mile and it's a dead heat.

They then race again pulling a caravan. They still have same power and same weight but the deisel will will win because it has more torque or pulling power. Bhp isn't the be all and end all. That's why the yanks like their big v8's.

Also, cars with higher bhp and not loads of torque tend to have a power band of some sort where the car pulls better. Cars with bags of torque tend to pull hard all the way through the rev range.
 
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so basically we all need cars with high revving V8's to make sure we got all bases covered (y)
 
Used to drive an 07 Mini Cooper S:

175 BHP @6000 rpm and torque of 162 ft/lb @ 4000rpm. 0-60 mph was 7 seconds, power to weight 147 BHP per ton.

I now drive a 2010 Honda Civic Type R:

200 BHP @7800 rpm and torque of 142 ft/lb @5600 rpm. 0-60 mph is 6.6 seconds, power to weight 152 BHP per ton.


All i know is that the Honda requires me to drop a gear to get an overtaking pull, when i drove the mini i used to just use the lower rev torque in the same gear.

No need to get tied up in power/ torque/ gear ration issues unless you tow trailers/caravans/boats or you are in to driving track days or off road.
 
wookey said:
Sorry Adam forgot about this thread!

Nice bike mate, looks like you've had a lot of fun with getting it usable! lol

How did the get the data on the test run?
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:)

Thanks yeah lots .... You've heard about them then... lol



I was using an electronic accelerometer data logger combo, which pretty much records anything with a varying voltage ...like the throttle position/speed for instance...I think it was rated about 20-30 samples per second, which is plenty.
It also combined to provide all the 'G' data from the meters to work out the power, acceleration, lean angle and braking.... Much faster sample rate for that bit, cant remember now
Then in conjunction I'd use a high speed 'infra-red bench' type gas analyser to sample five different gases coming out of the engine. Pretty low sample rate compared so there is a little delay correcting in the maths, hence the smooth gas results displayed. - Over all plenty of accurate information about what really going on and pretty much the only true way of testing a ram air system I decided. ...Really a hobby that got carried away would be more like it. ;)
 
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OT, but any more info on the gas analyser Forbiddenbiker? sounds like it could be very useful when mapping my next project :)
 
Byker28i said:
corrected for you ;)
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Nah, you just need the new 5-litre Ford Boss 302 V8 crate engine (available next year - currently powering the new 2011 Boss Mustang) - 500bhp normally-aspirated. Bung a FRRP 'charger on it and it'll push out 600 easily.

For less than $6,000 delivered...(y)
 
gman said:
Would anyone be able to describe what each of these actually are and more importantly the effect they have with cars? Layman's terms if possible!

I have a basic understanding from reading up online, but would prefer to hear someone's own words who really knows about it all. :)
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you want more torque than BHP, more of both is good, developed as low in the rev range as possible.
 
Forbiddenbiker said:
So err ...what you building? :D
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Cheers

We have a formula student team here at work/uni and I'm sure they need a gas analyser for tuning their cbr600 engine :) (has to breath through a single 20mm restrictor but we have a nice Motec M800 to do the sums for us).

I however am looking at building a clever ignition system (ion sensing hopefully with DSP to actively tweek timing) for my car. I currently have the honda integra type R but I'm looking for something a bit bigger with turbos, maybe a mitsi galant/legnum next. Big reliable power is all about accurate ignition IMHO so that is what I'm trying to do, can't find a commercially available unit clever enough to do what I want so I feel a project coming on. I'll be happy with the mitsi 2.5l V6 pushing 600+bhp though.
 
Ive just looked up that Motec, pretty impressive, I think I might try one of those... the same funtions ten years ago and you'd need a PHD to program it.

Good luck with your experimentation, sounds like lots of fun ... that analyser is very easy to work with, pretty tough too.

.. Yeah I agree, ignition retard is everything... get a big fat mix in, light it at the right moment and you could make lots of power.
 
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Arkady2 said:
Nah, you just need the new 5-litre Ford Boss 302 V8 crate engine (available next year - currently powering the new 2011 Boss Mustang) - 500bhp normally-aspirated. Bung a FRRP 'charger on it and it'll push out 600 easily.

For less than $6,000 delivered...(y)
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Hmm, if a SBC was available at those specs and that price it would make building an Ultima a realistic prospect. The cheapest 500bhp engine Amerspeed have on their Ultima list is double that.
 
at risk of starting a massive argument... Petrol?? PAH! with its laughable torque figures!! lol

Its all about Diesel!! 300lb/ft as standard with some modern engines!!

**Runs away and hides!!**
 
puggie said:
Cheers

We have a formula student team here at work/uni and I'm sure they need a gas analyser for tuning their cbr600 engine :) (has to breath through a single 20mm restrictor but we have a nice Motec M800 to do the sums for us).

I however am looking at building a clever ignition system (ion sensing hopefully with DSP to actively tweek timing) for my car. I currently have the honda integra type R but I'm looking for something a bit bigger with turbos, maybe a mitsi galant/legnum next. Big reliable power is all about accurate ignition IMHO so that is what I'm trying to do, can't find a commercially available unit clever enough to do what I want so I feel a project coming on. I'll be happy with the mitsi 2.5l V6 pushing 600+bhp though.
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For formula student we ran a cbr600 on a motec m400 a few years back, a very good bit of kit, very powerful you can run traction control through it with a couple of wheel speed sensors on the rear wheels. I ran a decent wide band lamda on the dyno to set it up. I never got round to running it without the restrictor, which was a shame because our formula student car was msa legal and logbooked!
 
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