My Clio on the dyno

Been on the dyno some weeks ago..

191 HP and around 200 Nm

Quite pleased with the result actually, as the dyno dynamics dyno certainly doesn't give the HP's for free!! (Focus RS stock only had 265HP on the same dyno as my car was on by the way, obviously this guy wasn't too happy about it!....)

Not bad for my (fully stock) 197 (with 23k km's on the clock!)

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The Units:

1HP = 736w
1BHP = 746w

where Renault refers to 172/182/197/200 etc
They are talking in HP (which is actually an electrical measurement of power)

So 197*0.736 = 145kW

If your car makes 192BHP
192*0.746 = 143.2kW
 
His car produced 208Nm which equals 153,5 lb/ft.

Most stock cars produce between 138 lb/ft (186Nm) and 145 lb/ft (196Nm) and between 184hp and 192hp on a dyno which is quite a bit less than what Renault claims.
This of course is perfectly normal because there is no air pressure when you measure the power on a dyno.
The blowers in front of the dyno offer cooling but not pressure.
You could compare it with sticking your head or hand out of the window while you're driving (you can feel the air pressure against your hand/head) or putting your head or hand in front of a fan (in which case you just feel the air with little to no pressure).

Air pressure is essential for an N/A petrol engine.
Which is why they call it an N/A engine.
An engine that depends solely on atmospheric pressure to draw in combustion air. This is in contrast to a forced induction engine.

So, take away most of the air pressure and you get lower results.
This, of course, means that when you're driving on the road, you will see higher numbers compared to your dyno result.

There are of course other factors that also determine your dyno result and most importantly the differences between so many dyno results.
These factors are the brand of dyno that you use to do the runs on and last but not least, the dyno operator.

If I recall correctly, the RS Wouter did the runs on is a Dyno Dynamics and they did the run in shoot out mode.
This means that no corrections are being used.
There are quite a few experienced people who think this is an optimistic way of measuring power and torque because no corrections are made while measuring the power of the car.

Anyway, that's the reason why I told Wouter that his torque number is high.

Sorry for the length of this post.


Kind regards

Der Abt

I know.....................
 
Many chassis Dyno's give unrealistically high figures, this is usually because of the flawed methods they use to estimate flywheel figures and also due to the operators interfering with the test

the Dyno Dynamics chassis Dyno's are often regarded as a dyno that reads less - but in reality it is the Dyno that reads correctly

this is a test of a car that was tested on engine dyno and then again on a Dyno Dynamics chassis Dyno

the Engine Dyno said 500 hp, the Dyno Dynamics estimated 503 hp ! pretty damm close on a 500 hp car

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this is an independent test that was done on one car on the same day on many different dyno's - its a long read but worth the time, Most of the Dyno's over read by a significant amount - the Dyno Dynamics machines were very accurate and would have made identical reults if the operators had tested the car in the same gear

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"If I recall correctly, the RS Wouter did the runs on is a Dyno Dynamics and they did the run in shoot out mode.
This means that no corrections are being used."

this is incorrect - the Shootout mode uses a very tight correction factor


The Torque of the vehicle is calulated from the power it makes and also the rpm that was used to record the power

if there is an error in the rpm, there can be an error in the Torque

there will never be an error in the HP

hope this makes sense

Regards