[outofphase]

I've done some searching but have come up with conflicting and/or vague answers. I drive a 2015 335i xdrive and it's actually my first automatic car ever. In my search I've seen people cutting average around 2 second 60ft's, shouldn't better 60 foots be possible with xdrive? In my old WRX I was able to cut a 1.7 every now and then with just bolt ons.

I plan on going to the track soon and just want to come up with a plan of attack.

I've tried the launch control feature but it feels like the revs are set too low for the best 60ft.

Do y'all use launch control? Just brake and rev? Start in N and slam it into drive?

Any tips would be greatly appreciated!

[ASportLineGuy]

I would never go from N to Drive to launch a car.

I drive the same year and model as you, and I have found great launches from launching around 1.8-2.1k RPM(Holding brake then releasing) . Feels better than LC, IMO.

[SBM1206]

Originally Posted by outofphase

I've done some searching but have come up with conflicting and/or vague answers. I drive a 2015 335i xdrive and it's actually my first automatic car ever. In my search I've seen people cutting average around 2 second 60ft's, shouldn't better 60 foots be possible with xdrive? In my old WRX I was able to cut a 1.7 every now and then with just bolt ons.

I plan on going to the track soon and just want to come up with a plan of attack.

I've tried the launch control feature but it feels like the revs are set too low for the best 60ft.

Do y'all use launch control? Just brake and rev? Start in N and slam it into drive?

Any tips would be greatly appreciated!

You may want to check Edmunds testing of 340 xDrive.
The acceleration technique should be the same.


Here are their comments:
Our fastest acceleration was achieved without launch control, as launch control limits engine rpm to 2,500 and this model has all-wheel and doesn't have to worry about wheelspin. To activate launch control, one must select Sport+ drive mode with sport shift selected. Launch control will not activate if sport shift is not selected. Then, while pressing the brake with your left foot, floor the accelerator with the right. A small launch control icon with activate in the gauge cluster if you did it right. As mentioned before, there is no wheelspin on launch, so not using launch control and letting the RPM rise slightly higher (to about 2700) is advantageous for the launch
https://www.edmunds.com/bmw/3-series...ce-tested.html

Looks like their experience is very similar to yours.

[outofphase]

Originally Posted by JoshyDeee

I would never go from N to Drive to launch a car.

I drive the same year and model as you, and I have found great launches from launching around 1.8-2.1k RPM(Holding brake then releasing) . Feels better than LC, IMO.

Thanks! Like I said, first automatic car This is a good thing to know not to do. Sad to say I'm learning this in my 30s!

[outofphase]

Originally Posted by SBM1206

You may want to check Edmunds testing of 340 xDrive.
The acceleration technique should be the same.


Here are their comments:
Our fastest acceleration was achieved without launch control, as launch control limits engine rpm to 2,500 and this model has all-wheel and doesn't have to worry about wheelspin. To activate launch control, one must select Sport+ drive mode with sport shift selected. Launch control will not activate if sport shift is not selected. Then, while pressing the brake with your left foot, floor the accelerator with the right. A small launch control icon with activate in the gauge cluster if you did it right. As mentioned before, there is no wheelspin on launch, so not using launch control and letting the RPM rise slightly higher (to about 2700) is advantageous for the launch
https://www.edmunds.com/bmw/3-series...ce-tested.html

Looks like their experience is very similar to yours.

Much appreciated. I'll give that a shot messing with the RPMs.

[ASportLineGuy]

Originally Posted by outofphase

Thanks! Like I said, first automatic car This is a good thing to know not to do. Sad to say I'm learning this in my 30s!

Better to learn now then never haha!

I feel like there are so many different ways to launch our car, and you could always rev it up higher and try that.

Unless im really trying to get a great launch I dont even hold the brake, ill just floor it.

But when I do want a smooth launch/quicker that is quicker than just flooring it, the 1.8-2.1k launch worked well. Let me know what works best for you

[Wires]

You will find if you are at idle and just "slam" the gas, the car will torque limit with a poor launch. Slight roll and then aggressively accelerate will work better than the hammer it from a dead stop.

Pre-loading it with the brake/gas will be better, but this (as well as LC) is insanely hard on the torque converter and transmission fluid since you are basically stalling the converter at a decently high load.

[hardparker]

I brake torque it and launch around 3000 RPM, give or take 100. I typically see 1.7 to 1.8 second 60 foot times.

[upsidedownfunnel]

Generally, with a torque converter/planetary gear automatic transmission, you want to "brake torque" which is a method to multiply your torque by "winding up" your torque converter. You do this by slamming on the brakes with your left foot and modulating the gas with your right foot at a particular engine speed (RPM). This is almost always the best way to launch any standard automatic transmission car. Some, like the sport automatic transmission BMWs have a launch control which optimizes what engine RPM the car holds.

Essentially, what you're trying to do is increase wheel torque just until you get chirp in your tires. You want to get all the way up to the point JUST BEFORE you spin your tires. That's the absolute best you can do.

[sspade]

Launch Control.

[vooonoo]

Originally Posted by sspade

Launch Control.

This