Down on power on dyno

[C19WKR]

Hi guys, i had my 67plate A45 w176 in at Ecotune for a remap today.
On the 1st dyno run they showed me that it really down on power at 340bhp (standard 381)

They mapped it to see if it was a faulty remap done previous and it never helped, so they gave the car a few checks and it seems to have a problem with the exhaust pressure.
I have booked it back in to get checked over in a few weeks.

Has anyone had any similar issues or ideas what this could be?

 

[AMGeed]

How are they reading the output?
If the reading is 340bhp at the wheel, that correlates to 390bhp at the flywheel which is where most figures are posted.
This is assuming a 15% loss at the wheel and corrected (340 x1.15) =390

 

[C19WKR]

How are they reading the output?
If the reading is 340bhp at the wheel, that correlates to 390bhp at the flywheel which is where most figures are posted.
This is assuming a 15% loss at the wheel and corrected (340 x1.15) =390

Thanks for the reply, it says max clutch power 340.40

 

[rf065]

Who's to say 340 on their dyno would not read 380 on another dyno?
Some dynos are always reading more or less than others. Can they prove that theirs is more accurate?

 

[GeeJayW]

Hmm... good luck

 

[C19WKR]

Who's to say 340 on their dyno would not read 380 on another dyno?
Some dynos are always reading more or less than others. Can they prove that theirs is more accurate?

Well thats the thing mate, whos to know for sure, but they can sell stage 2 on their website providing 460bhp so if they can get me near that i wont be complaining, Ecotune are a reputable name in this business id think.
I trust them to look at my car in a few weeks and help me out to get to the power they provide

 

[whitenemesis]

I think dyno figures are only good for comparisons of before and after on the same machine, not for absolutes

 

[Doodle]

As the age old phrase goes - Lies, damn lies, statistics and dyno figures.

 

[Teego]

Is the standard quoted power in bhp, hp or ps?

 

[ALFAitalia]

Does not matter ....Hp and bhp are the same....and PS is 98 percent of a horse power.... so all near enough the same.

 

[SpikyMikey]

Does not matter ....Hp and bhp are the same....

Kind of, but kind of not...

 

[ALFAitalia]

The units themselves are EXACTLY the same.....the difference is that HP or horsepower describes the total amount of power an engine can produce. So the higher the HP, the more power the car has and the faster the top speed. BHP or brake horsepower is usually used as a more realistic measurement as it considers the power left over after the gearbox, alternator and water pump are working as well as any loss of power due to friction. So basically the same units measured at different points.....and since most dynos allow a certain percent for loses depending on the model and cant measure power at the crank directly.....they are for all intents and purposes, the same.
As said above most dynos are good for comparison only....because depending on the formulas the user inputs, you could take your car to 4 different dynos on the same day and get 4 different power measurements!!!

 

[Bellow]

Inertia dynos - the type that take their measurements during an acceleration run have no right to cite HP as BHP as there is no brake. BHP is only correct when the dyno is a brake type that loads the engine to the point where it can no longer gain rpm.

 

[Bobby Dazzler]

Hi guys, i had my 67plate A45 w176 in at Ecotune for a remap today.
On the 1st dyno run they showed me that it really down on power at 340bhp (standard 381)

They mapped it to see if it was a faulty remap done previous and it never helped, so they gave the car a few checks and it seems to have a problem with the exhaust pressure.
I have booked it back in to get checked over in a few weeks.

Has anyone had any similar issues or ideas what this could be?

Which fuel do you use, and what’s the octane rating?

 

[C19WKR]

Which fuel do you use, and what’s the octane rating?

It was tesco momentum 99

 

[Bobby Dazzler]

It was tesco momentum 99

I would say there’s something not right with either the car, the dyno or the operator. Before spending on diagnostics and replacement parts try it on another chassis dyno without telling the operator that you believe it will be down on power and see what comes out.

 

[C19WKR]

I would say there’s something not right with either the car, the dyno or the operator. Before spending on diagnostics and replacement parts try it on another chassis dyno without telling the operator that you believe it will be down on power and see what comes out.

Yeah thats not a bad idea

 

[Petrol Pete]

PS = Pferdestärke = Horsepower in German.

Just in metric , as said , to a factor of 0.98

 

[ALFAitalia]

0.98632007 to be accurate!

 

[Petrol Pete]

No dyno is THAT accurate !