R56 Dyno Results

I have just had my R56 Cooper S rolling road tested on one of the best Dyno's in the UK (top respected in the country) and these are the results I got.
As I am used to N/A cars, I am used to cars which produce power all the way to the redline, whereas going off this dyno graph, you can see that I am losing power from 4000rpm onwards... is this normal of R56 Cooper S cars?

The mechanic said it looked a bit weird, even for a turbo car to lose power so early on in the rpms range, as redline is at 6500, everything between 4000 and 6500 is losing power quickly...

Has anyone had their R56 dyno'd and seen anything like this?
Mod wise, I have the following:

Remapped ECU
TBE
DDMWorks CAI

I am getting 225bhp - which seems very good - Im happy with that, but just wished the car would continue to make power past 4000rpm...Any ideas? Does it look like there is a problem or is this just the nature of the R56 turbo?

Thanks



ps - just to clarify. The line which starts at 1000rpm is the torque line (and shows how the overboost feature works nicely , and the line which starts at 3700rpm is the bhp curve)

 

i WISH i was getting 225 at the wheels!! ive never tested my car though. i have an alta CAI but what ECU remap are you using? is it reliable? how long have you had it? please give me more info on that.

i notice that same thing with my car. peaks around 4000-4500. i like that actually. my NA 350Z would pull the same at 1500 as it would 6500 and thats boring, it had no sweet spot, no reason to shift and work the power band. i was either on the gas or off the gas.

 

My 225 isnt at the wheels Im afraid! we measure bhp at the flywheel over here in the UK
Again, my ECU remap is a UK Company (called P-Torque if its of any use)

I prefer a car to drive progressively, ie to continue making power (more and more) the higher you rev it (as with the old R53 S)

 

That looks normal for an R56 from what I have seen. The turbo is rather small allowing for quick spool and good power at low to mid RPM levels but it runs out of breath over 4K and beings it's downward slope.

 

yeah, come to think of it my R53 2004 did pull hard all the way up.

 

it would be perfect if there was a way to keep it going to say 5500 and for it to then start its downward slope :(

 

Pretty nice numbers!

Question though, do you know what your Air/Fuel ratios are like? I'd be interested to see what your tune did for them.

 

Im afraid I dont know my A/F ratios mate - sorry. The Dyno graph doesnt show that information

 

I think because the turbo is so small that it runs out of breath pretty soon. You can clip the turbine wheel and move the powercurve up more if you race it and are in the higher RPM range while racing.

15% drive train lost is a base figure from engine vs wheel hp.

 

makes sense. Its very hard to have lots of downlow reponse while still having a great top end. Twinscroll should allow a bigger turbo to have more response downlow while still having a good top end. At least you're still making horsepower as you rev it out, eventhough the torque is decreasing.