View Single Post
      10-18-2012, 04:21 PM   #23
BPMSport
BimmerPost Supporting Vendor
BPMSport's Avatar
United_States
3387
Rep
7,541
Posts


Drives: Harrop M3 / F10 M5 / F82 M4
Join Date: Apr 2008
Location: SoCal

iTrader: (9)

Garage List
2000 BMW M5  [0.00]
1990 BMW 735i Turbo  [0.00]
2008 BMW M3  [7.50]
2015 BMW M3  [0.00]
2015 BMW M5  [0.00]
Quote:
Originally Posted by CanAutM3 View Post
I would personally trust the dynapack more in terms of accuracy and repeatability as they are actual "brake" dynos similar to what we use in the aerospace industry and what auto manufacturers use to develop engines.

From what I understand, dynojets and dynapacks would use very different calculation methods to establish power ratings. I believe overall drivetrain inertia can have much less impact on a dynapack since it is a brake dyno and does not rely on a drum's inertia to load the engine, it all depends how fast/slow the operator sets the acceleration rate. Further, there is also no loss due to tire deformation and slippage at the tire/drum interface. IMO it is normal and expected to see different absolute numbers on both dynos.
Exactly. It was an interesting experience for me since I'm so used to using DynoJets and Dyno Dynamics.

I will be heading back to that dyno in the next week or so to finalize the Stage II X5M tune. I wish we got the gains that car gets! I'm estimating 80WHP and 120FT/LBS torque.

Edit:
Gains were ~100whp and ~125wtq..
Attached Images
 
__________________

-----| Like us on Facebook | Instagram || Tuning Information | Remote Coding |-----
----Visit us at www.BPMSport.com - Emotion. Driven. | Toll Free: (888) 557-5133----

Last edited by BPMSport; 11-24-2012 at 01:43 PM..
Appreciate 0