Power, Torque and rolling roads

[arkamelis]

R.i.p

 

[markbe]

SL600 Biturbo Kleemann on the Rolling Road.

Hi all, I am about to upgrade my SL600 so firstly I checked the current power.
I used Car Plannet's rolling road, safe to 2400bhp!!, in Warrington.
Results below.
First I will add an LSD and change will be the exhaust to 3" piping and 100 cell
cats.
Will show the results when done.
Mark.

 

[SAFC]

Super synopsis. 10 out of 10.

 

[amg_me]

yes well done

 

[Rovinghawk]

can you explain the laws of coefficients of friction in the same laymans terms .....especially the bit regarding tyre widths ignoring the rules and providing more grip with a larger contact patch that one really fazes me a little.

At the risk of sounding offensive, that's wrong.

Contact patch area= weight of car/car tyre pressures. Width of tyre doesn't alter the area, just the shape (ie wider but shorter).

What affects grip is hardness of the compound & (unlike most friction materials) how much it deforms under load. Rubber bends and abrades more than most friction materials, so extremely soft coompounds can give less grip under certain conditions.

It's a long, complicated subject with too many variables for a layman's description; I don't understand it all either.

RH

 

[Gazza55]

Rolling Road Dyno,s

TDI Lakeside
V good and know their stuff, AMD next door (not recommended)

 

[Horrgakx]

I'm sure that for my W210 E55 AMG, dyno mode is a myth. I've asked and asked, even been promised the 'how to' but it's all proved fruitless.

The nearest I've got to switching it all off is pulling fuse no. 11 under the rear seat. But the car doesn't like it and throws a load of warnings up, then it takes ages to settle back down when the fuse is replaced.

 

[Miley Tipton]

Hi,
I am new to this Forum,and want to explore more thing related to automobile technology, this thread is related to same, So i think, I will be able to learn new thinks
My father and I Work in a Garage, We generally face problem related to power and pick up. I mean when where we do something to increase the pick up of the Car, It never give us proper milleage after that, or sometime, It stop when it slow down. If some one could suggest me something related to this, please do reply.


Thanks and regards

 

[johnpidge]

TDI Lakeside
V good and know their stuff, AMD next door (not recommended)

Beware AMD - Suggest Torque of the Devil

 

[deen-paula]

We're not going to go through all the equations and physics of how horsepower and torque are calculated, not only is it difficult to explain in writing, it confuses the hell out of most people. Unless you plan on being a specialist engine technician, it’s just too much. But we will try to explain what they are, how they relate to each other and how it affects your cars performance in the simplest way we can.
Horsepower
The term horsepower was first used on engines by James Watt, a British inventor, who was associated with steam engines. James Watt used the term to measure steam engine power to the power from a horse. Horsepower is the rate at which work can be done (over a given distance). A horses’ workload was measured to calculate a starting figure for the measurement of this power. Incidentally engine power can also be measured in kilo Watts (kW) and (PS) pferdestarke which is German for horsepower.

1HP = 746Watts = 1.01387PS

The familiar Brake Horsepower (BHP) means that power was measured using a dynamometer. BHP is measured at the crankshaft. Car manufacturers, normally quote this as ‘peak’ horsepower (the maximum horsepower possible at a given rpm).
Horsepower is a measurement calculated from the engines torque which is multiplied by a given RPM and then divided by 5252. 5252 is the figure used for the calculation; it is a constant and unless you want to be bored/confused, just take it from me.

Torque * RPM
Horse power = ------------------
5252

We were going to mention rolling road dyno’s, but due to the differences from one dyno tuner to the next, feel you are best off seeking advice from the tuner themselves. The main reason we're not going to mention anything here is the many ways in which the dyno tuners adjust the figures to calculate for drive loses. Also remember the car is stationary and not on the open road, with air pressure, temperature changes and much more not taken into consideration.
Torque
Torque is the turning force, in this instance we are talking about the turning force that will be applied to the driving wheels of the car, measured by the units, pounds-foot (lbs-ft) or Newton-meters (Nm). A lb-ft of torque is a measurement used which represents for example the turning force at one end of a 1ft bar while at the other a 1lb weight is suspended. Therefore if you have a 200lb weight on the end of the 1ft bar, you will have 200lbs-ft of torque. Obviously as this number rises, the more turning force there is on the wheels.

1 Lb-Ft = 1.36 Nm

As you can see, torque will be useful for those who like to tow things, as a heavy vehicle will benefit from that extra torque.

Torque is a measure of the ability of an engine to do work (in an instance).

However it is important to realize that as you increase the torque of your engine, hence increase the turning force of the driving wheels, you run the risk of just spinning your wheels. This is quite common on high powered front wheel drive (FWD) cars with lots of torque. With the front wheels also designed oddly enough to steer the car you will get something called torque steer, while you are turning your steering wheel and accelerating, you end up spinning the front wheels and not much happens with the steering either. Of course any high powered car with lots of torque will spin the wheels due the forces of nature (turning forces vs traction). By dividing that torque to all 4 wheels (4WD) you can reduce the spin of a high torque car and transfer the power to the road better, hence EVOs’, Imprezas’ and Skylines’ etc tend to be able to pull away from a stand still quite well, although there are many more factors that can help a FWD or rear wheel drive (RWD) car to put that power down effectively, such as tyre size/compound, suspension/chassis setup and gear ratios.

 

[steven_tyler]

At PDT we take rolling road tuning seriously. We are the proud owners of one of the world's finest 4wd Chassis dynamometers - Dyno Dynamics.
Our state of the art 450 series 4wd dyno has the potential to measure and accurately graph a massive 1200 HP and 1600 lbs/ft of torque! Not only is the dyno capable of measuring massive power it is also regarded as the the most accurate chassis dyno available.
Due to the supreme accuracy of the Dyno Dynamics rolling road, BHP & Torque measurements can repeatability be made to an accuracy of 0.1 BHP and 0.1 Ft/Lb.
Dyno Dynamics rolling roads feature an electromagnetic retarder (Eddy current) that allows a precise load to be applied to the rollers and hence the car under test. This load can be used at steady speed as well as during acceleration. The load can be easily varied to simulate any road or track condition. For example, The dyno allows us to hold a vehicle at say 50% throttle and 3,500 RPM while optimizing the air to fuel ratio or timing. Using this extremely controlled environment we can achieve a properly tuned vehicle for part throttle driveability as well as maximum performance at full throttle!

We are happy to give free no obligation quotations for all of the services we offer. If we can't provide the service that you require then we will be happy to point you in the direction of someone that does!

 

[Beno]

Sorry, that's not entirely true i work at a research centre and we have 2 4wd chassis dyno. However there not open to the public

 

[dewitt-joyce]

Rolling RoadToday's cars have to be tuned in a controlled environment. We operate 2wd and 4wd Rolling Road Test Facilities with data logging.

We have at our premises two fully equipped dyno cells.

One containing a state of the art MAHA LPS 3000, 4wd Dynomometer.

And an additional Maha LPS 13 2wd Dynomometer.
POWER RUNS

Want to see how much power your car is putting out?

We offer 2wd Dyno run @ € 60.00
We offer 4wd Dyno run @ € 100.00

Power runs include a print-out of your full power & torque curves.

Our technician will give you advice on how your car is performing and if any additional improvements can be made
Club Rolling Road Days

We have Club Rolling Road Days on various Saturdays during the year. Each participant brings their car along for a power run - to see who has the most HP & Torque. We supply tea/coffee/soft drinks munchies & additional catering can be organised by prior arrangement. Special sponsor prizes also available. Min. 10 cars per RR Day.
ECU MAPPING & ENGINE TUNING

Our Tuning Services, depending on your engine requirements can vary from a power test to optimising Ignition, Fuelling, Cam Timing etc. to get the best power from your engine.

Rolling RoadWe offer Supply, Installation and full re-mapping of aftermarket ECU's for increased power & torque and improved
drivability. From Fast Road to Full Race,

Details of ECU's we can supply and or map.

* EFI
* OMEX
* AUTRONIC
* DASTEK UNICHIP.
* APEXI
* Gems
* Motec

We offer Full Competition Engine Tuning


Weber & Dellorto Re-Jetting & Tuning

 

[steadyeddie]

Where are you based?

 

[keith-o]

Torque
Torque is the turning force, in this instance we are talking about the turning force that will be applied to the driving wheels of the car, measured by the units, pounds-foot (lbs-ft) or Newton-meters (Nm). A lb-ft of torque is a measurement used which represents for example the turning force at one end of a 1ft bar while at the other a 1lb weight is suspended. Therefore if you have a 200lb weight on the end of the 1ft bar, you will have 200lbs-ft of torque. Obviously as this number rises, the more turning force there is on the wheels.

1 Lb-Ft = 1.36 Nm

As you can see, torque will be useful for those who like to tow things, as a heavy vehicle will benefit from that extra torque.

Torque is a measure of the ability of an engine to do work (in an instance).

However it is important to realize that as you increase the torque of your engine, hence increase the turning force of the driving wheels, you run the risk of just spinning your wheels. This is quite common on high powered front wheel drive (FWD) cars with lots of torque. With the front wheels also designed oddly enough to steer the car you will get something called torque steer, while you are turning your steering wheel and accelerating, you end up spinning the front wheels and not much happens with the steering either. Of course any high powered car with lots of torque will spin the wheels due the forces of nature (turning forces vs traction). By dividing that torque to all 4 wheels (4WD) you can reduce the spin of a high torque car and transfer the power to the road better, hence EVOs’, Imprezas’ and Skylines’ etc tend to be able to pull away from a stand still quite well, although there are many more factors that can help a FWD or rear wheel drive (RWD) car to put that power down effectively, such as tyre size/compound, suspension/chassis setup and gear ratios.

 

[s3lin1]

Well done with these info,really helpfull