Quote:
Originally Posted by terahertz
Hi Cary,
I've been poking around the editor because I am curious but some things are just not self explanatory.
How did you know that the exhaust flaps 1-8 was for different car models?
Also, on burble cold/warm, the x axis says %. % what? It goes from 11.8% to 170%. And what's the Z axis? -32 burble doesn't really mean much to me.
Is there some online resource that explains these things? I don't mean a tuning class, but the terms and details that aren't exactly self explanatory. Or are these just normal things in BMW tuning?
Thanks  |
Exhaust flaps are what's part of so called 'sound tuning'. They are independent based on convertible or not, transmission and mode you're in.
As for load, here we go, too geeky for most and really not too important to know all these details, but since you're asking
Quote:
Load % = [current airflow] / [(peak airflow at WOT@STP as a function of rpm) *
(BARO/29.92) * SQRT(298/(AAT+273))]
Where:
- STP = Standard Temperature and Pressure = 25 °C, 29.92 in Hg BARO,
- SQRT = square root
- WOT = wide open throttle
- AAT = Ambient Air Temperature (in °C)
There's also relative and absolute engine load values. Difference between the two?
You've seen the above equation for calculated engine load. Below is the calculation for absolute engine load:
Load Abs = [air mass (g / intake stroke)] / [1.184 (g / intake stroke) * cylinder displacement in liters]
Derivation:
- air mass (g / intake stroke) = [total engine air mass (g/sec)] /
[rpm (revs/min)* (1 min / 60 sec) * (1/2 # of cylinders (strokes / rev)]
- Load Abs = [air mass (g)/intake stroke] / [maximum air mass (g)/intake
stroke at WOT@STP at 100% volumetric efficiency] * 100%.
Where:
- STP = Standard Temperature and Pressure = 25 °C, 29.92 in Hg (101.3 kPa)
BARO
- WOT = wide open throttle
The quantity (maximum air mass (g)/intake stroke at WOT@STP at 100%
volumetric efficiency) is a constant for a given cylinder swept volume.
The constant is 1.184 (g/liter 3) * cylinder displacement (liter 3/intake
stroke) based on air density at STP.
This equation relies on the flow of air and basically engine displacement. This correlates with VE (volumetric efficiency), basically how completely a cylinder fills with air on the intake stroke at WOT.
|
Hope the above is a fun read
Quote:
Originally Posted by Jadar
I once heard Dzenan reference to it as bootmode not 100% but he will have to chime in.
|
Spot on. Its pronounced bootmode but funny enough that's rarely the pronunciation used by most.
Turned out most people ended up calling it BM3 or bootmod.