Petition about clio power figures...

[BenW]

Dyno dynamics RR pretty much guess the fly figure, it's an informed guess but what if the drag from the clios box is higher than estimated? That could be why the power figures are low in some cases.

The fly figure isn't really guessed, they calculate it based on how quickly the rollers slow down which gives an indication of transmission losses (engine braking) as far as I know.

And I'm not sure why people are saying all cars produce less power than stated? There are just as many cars that produce more power, cheaper hot hatches are a prime example where manufacturers want to sell a fast car with a low insurance bracket which means making the figures look worse.

 

[Foxspeed]

The fly figure isn't really guessed, they calculate it based on how quickly the rollers slow down which gives an indication of transmission losses (engine braking) as far as I know.

And I'm not sure why people are saying all cars produce less power than stated? There are just as many cars that produce more power, cheaper hot hatches are a prime example where manufacturers want to sell a fast car with a low insurance bracket which means making the figures look worse.

i have only been to 1 rr where that has been done properly...

 

[dangerdaz]

What is this goin to achieve? Like previously mentioned the RR is only producing and approx figure. So you dont know what the car is making at the flywheel. Even if Renault did say, "ok, the car doesn't produce 200 ps." then what? What's your goal?

You'll be moaning about the claimed fuel consumption next.

Not moaning at all. Just an idea to throw at Renault to get a response from them..If it appeared there was an hp problem.
I 'wrongly' assumed that the majority of cars are underpowered but have been proved incorrect. Happy to admit my mistake. 8)
Part of the reason i like this forum is always nice to get peeps opinion.

 

[Richy_Boy]

Every Dyno Dynamics RR I've been to have done a full run-down to work out (rough) transmission losses. IF the dyno is setup correctly, uses real humitity, temp and gearing figures, it's normally pretty accurate when compared to a proper engine dyno. Personally, if there's a trend that nearly ALL cars are 10bhp down on the advertised hp figure, then I think that's a bit cheeky of renault to knowingly lie about, lets face it, a key sales driver for people to choose a 200 over, say a 197!

With that said, these engines seem to take a bucket load of miles to be at their best.. i.e. 20-30,000 miles!

More annoying to me though is the claim mpg figures which are outragously generous, but then all manufacturers seem to set the car are to 'cheat' their way through the EU tests, rather than give accurate figures. I'd like to see an Renault executive/engineer or boffin drive a RS 200 and obtain any of those claimed figures! The best I've had so far is 35mpg cruising down 40-50 roads, then turned onto the M4 and it went DOWN to 31mpg! (probably down to gearing)

Rich

 

[DanT]

As Ben said ive had mine looked at by Matt at TDF and upon first runs before the remapping i made (the clio ) 187bhp on Momentum99 fuel. Interestingly he did ask what i fuel i was using as it can make a small difference in top end power he said.

After mapping we did some more runs and it made 193bhp which i was very pleased with to be honest.

Cars just dont make their claimed figures i guess!

 

[PB.200]

The fly figure isn't really guessed, they calculate it based on how quickly the rollers slow down which gives an indication of transmission losses (engine braking) as far as I know.

And I'm not sure why people are saying all cars produce less power than stated? There are just as many cars that produce more power, cheaper hot hatches are a prime example where manufacturers want to sell a fast car with a low insurance bracket which means making the figures look worse.

Not on a dyno dynamics!!

It is simply a % added on.

A dastec is a run down one and Foxspeed ran 202bhp on one!

 

[shakey_hand_man]

love this thread haha..

The problem is quite simple and its down to interpretation..

Renault quote flywheel power, that the engine can produce on the day (so get the dyno room as humid and cold as possible with a high air pressure and you probably would make 200bhp or there abouts)

When you get a car dyno'd the power figures are flywheel and are pretty darn accurate most of the time, although the figures listed are mainly din or iso as was mentioned earlier (effectively taking your 200bhp then reducing it to take your air pressure to a standardised figure probably 1bar, then reducing power further for humidity and air temp) this results in your final power figure looking somewhat lower than what the engine actually made.

The DIN and ISO figures are used as it makes it a lot easier to compare power and torque between dyno centres. The actual figures help sell cars

Just to give some comparison my car (rs200) was dyno'd and made: 188.8BHP DIN but actual power was 195.5BHP on the day. If I went back and got the car dyno'd on another colder damper day the DIN figure would stay the same but the actual power would rise further.

I would like to see all car manufactures have to quote DIN figures by law.. -that would mix things up a bit

-Andy

 

[Cannit]

Nice input Andy. Interesting too as not heard that before. Rolling road figures always get people talking on forums lol!

 

[ben_r1]

Mine was dyno'd in standard form at AmD Essex with 194bhp bang on. Was run in religiously.

EDIT: well 193.7bhp but you'll let me off the 0.3

 

[Willis]

Mine was dyno'd in standard form at AmD Essex with 194bhp bang on. Was run in religiously.

EDIT: well 193.7bhp but you'll let me off the 0.3

Within 0.2 of mine mate, I'd say the figures were pretty accurate or our cars were ran in properly or the rollers by some miracle were virtually the same!!!

 

[Paul]

I feel a petition about getting Renault to accept the pulling to the left issue would be better...

They will blame it on road camber and that will be that lol! TBH mine doesn't do it though.

I cant fault the Clio though lol

 

[GrumpyTwig]

You'd be surprised how rare a truly flat road is, the rare occasion I've been on one the cars goes completely straight.

I've also found tyres effect it quite a bit, possibly down to the tread design.

 

[Brown bear]

More annoying to me though is the claim mpg figures which are outragously generous, but then all manufacturers seem to set the car are to 'cheat' their way through the EU tests, rather than give accurate figures. I'd like to see an Renault executive/engineer or boffin drive a RS 200 and obtain any of those claimed figures! The best I've had so far is 35mpg cruising down 40-50 roads, then turned onto the M4 and it went DOWN to 31mpg! (probably down to gearing)

Rich

You need to read up about how mpg figures are achieved, it's easy to see why they fall short in reality. The problem isn't the manufacturers, it's the testing procedure.

 

[PB.200]

You can look at mpg claims 2 ways.

1 they lie and that's bad cos you can't achieve it.

2 be glad it's higher than true so your tax is lower. On true mpg a 200 would be £400 to tax.

 

[Foxspeed]

You need to read up about how mpg figures are achieved, it's easy to see why they fall short in reality. The problem isn't the manufacturers, it's the testing procedure.

the figures should only be use to compare car against car and not for what it would do in real life

all the cars are tested exactly the same way - something you DONT get with rolling roads...

 

[GlassJaw]

Rolling roads and dynos are for gains not pub power figures.

There are also soooooo many other factors that effect a cars real world performance and dyno readings other than just the powertrain.