[insanecoder]

Originally Posted by E90 LCI

Then why tf would BMW have launch control feature if it was that harmful to all of the car's components?

Pretty sure launch control was developed with expected operational torques in mind.. not the higher torque assoc w/ tunes
Even under normal operating torque launch control is still one of the ways to really stress your drive components

[Polo08816]

Originally Posted by E90 LCI

Then why tf would BMW have launch control feature if it was that harmful to all of the car's components?

Read the bolded part.

Launch control (if available) is designed around a stock powertrain.

Originally Posted by Polo08816

Clearly, it shouldn't be launched. Drivetrains generally don't do well with that type of shock regardless of vehicle type. There is no torque limitation for an instantaneous load like that. They will all eventually fail from that type of abuse. You keep doing that and you'll inevitably exceed the yield stress of something.

Put it this way. If you have an engine rated for 500 ft-lbs of torque and you dump the clutch from a standstill, guess what instantaenous torque the driveline sees? I can guarantee you it'll far exceed 500 ft-lbs.

Also, your analogy is terrible. Launches are abrupt and brutal on drivetrains. Proper braking technique (and weight transfer management) involves the driver being smooth in his braking inputs. You squeeze the brakes and then release instead of just punching the brake pedal - whether that involves threshold braking from triple digits to the point where you turn in or if you're trail-braking on entry into a turn.

If you're a fan of unskilled driving that involves going as fast as possible in a straight line, you should have bought a live axle domestic car. Those are generally less expensive to repair/replace inevitable blown components from drag racing.







Not surprised by this at all.

~82,000 miles on my 2014 335i RWD with an M Performance Limited Slip Differential with 14 track days on top of spirited driving. No drivetrain issues. But then again, I'm not abusing my car by launching it repeatedly either...


If the vehicle has launch control, you can launch an OEM/stock car pretty much all day long. You'd expect wear item life to decrease, but the hard parts should still be fine. If the car has launch control, it will be treated as a design requirement and included in the fatigue and fracture analysis and validation phases.

The problem is when you dramatically increase the torque output of the motor from the OEM/stock configuration.

But hey, this fact won't stop these clowns from modifying their powertrain and launching their cars anyways because it'll provide the forum with some serious LOL-ammo when their shit blows up and costs 4 plus figures to fix. It's always better to launch a modded car with massive torque because of the potential for explosive fail and hilarity.

This...

Originally Posted by insanecoder

Pretty sure launch control was developed with expected operational torques in mind.. not the higher torque assoc w/ tunes