Best launch technique on DCT not using LC?

[Fiebrudo]

Based on your collective experience, what is the best technique in order to obtain the fastest 0-60 time on a DCT car without using launch control (must admit, LC is awkward to use, not user friendly, and not readily available when needed )

[Sticky]

LC is user friendly, just not consistent.

There really is not much to it other than putting your foot on the gas. Just dont mash it down all the way so that it cuts power. In S5 with MDM the car will modulate the clutch and traction for you off the line. That is how I do it when not using launch control.

[White Shark]

Originally Posted by Fiebrudo

Based on your collective experience, what is the best technique in order to obtain the fastest 0-60 time on a DCT car without using launch control (must admit, LC is awkward to use, not user friendly, and not readily available when needed )

"Select M-Dynamic mode" (Tiff, Fifth Gear)

[icemang17]

S5 MDM works very well.....typically it revs to about 4k then sorta drops the clutch...not as aggresive as LC, but pretty fast

[swamp2]

Originally Posted by icemang17

S5 MDM works very well.....typically it revs to about 4k then sorta drops the clutch...not as aggresive as LC, but pretty fast

Yup. S5 (or D5 which makes perfect at redline upshifts everytime), MDM, suspension = comfort (which is still active suspension) and simply mash it. You will experience a small but noticeable lag as the car revs and the clutch gets going.

Also just to be clear this is a strong hunch more than something I can prove with instumented testing. That is what will really answer the question.

[footie]

Without a doubt the best way to launch your DCT car without using LC is the throttle the same way as you would to take off normally and once your clutch is engaged steadily feed the throttle in until full throttle is pressed (1/4~1/3 of a second). This gives less wheel spin and mega forward momentum.

Simply mashing the throttle only gives mountains of wheel spin plus that delay as revs build which swamp highlighted.

[skierman64]

Originally Posted by Fiebrudo

what is the best technique in order to obtain the fastest 0-60 time on a DCT car without using launch control

The best technique is to get rid of the convertible that weighs 400-500 lbs more than the coupe and sedan.

I have to ask, how is launch control awkward to use. DSC off, S6, gearshift forward, floor the throttle. It takes 5 seconds to get there, less if you have DSC off and S6 programmed into M-mode.

[swamp2]

Originally Posted by footie

Simply mashing the throttle only gives mountains of wheel spin plus that delay as revs build which swamp highlighted.

Absolutely not with MDM as I pointed out.

[adamr]

just floor the car in S6 mode with DSC off ... the car will build revs to about 4000RPM and then it dumps the clutch ... its like launch control without using launch control

its repeatable unlike the launch control method ...

[footie]

Originally Posted by swamp2

Absolutely not with MDM as I pointed out.

MDM is not the quickest way to launch the car but for a novice it's going to give the most consistent results.

My comments were for DSC off which on sampling both methods the mashing the throttle is not the best way, but it is the most dramatic,

[Fiebrudo]

Originally Posted by skierman64

The best technique is to get rid of the convertible that weighs 400-500 lbs more than the coupe and sedan.

How about: Best technique: Get rid of your M3 and get a GTR!! YOu are so bright and funny, HA, HA, HA!!! Anyway, thank you for your very insightfull recommendation!

You don't like my convertible? that is a shame. I have really enjoyed it so far, A LOT. As a matter of fact, I haven't had more fun driving a car in my life until experiencing the joy of hi-performance topless driving.

So back to the question: Is there a benefit of accelerating (to build revs) while holding the brakes before launching?

My point regarding LC, imagine the following scenario.

You are in a stop light, two lines will turn into 1 and a redneck bully in a RAM SRT truck stops next to you and you know he will do the impossible to cut you off (and he has tons of more torque than you and is feasible that will be faster to 30mph. You have only a few seconds before the light turns green. No way you are going to have time start pressing buttons, waiting for the checkered flag and so on (if it works at all as I read so many stories of LC failing living you revving the engine like crazy in neutral (embarrassing)

So press M button and ......

[Sticky]

Originally Posted by swamp2

Absolutely not with MDM as I pointed out.

If you mash it too hard traction control will cut in and the car will cut power. It is based on the traction the tires have available.

[Sticky]

Originally Posted by Fiebrudo

How about: Best technique: Get rid of your M3 and get a GTR!! YOu are so bright and funny, HA, HA, HA!!! Anyway, thank you for your very insightfull recommendation!

You don't like my convertible? that is a shame. I have really enjoyed it so far, A LOT. As a matter of fact, I haven't had more fun driving a car in my life until experiencing the joy of hi-performance topless driving.

So back to the question: Is there a benefit of accelerating (to build revs) while holding the brakes before launching?

My point regarding LC, imagine the following scenario.

You are in a stop light, two lines will turn into 1 and a redneck bully in a RAM SRT truck stops next to you and you know he will do the impossible to cut you off (and he has tons of more torque than you and is feasible that will be faster to 30mph. You have only a few seconds before the light turns green. No way you are going to have time start pressing buttons, waiting for the checkered flag and so on (if it works at all as I read so many stories of LC failing living you revving the engine like crazy in neutral (embarrassing)

So press M button and ......

You don't hold the brake and the gas with the DCT, you don't have a torque converter to load, it isn't an automatic.

[skierman64]

I didn't say I don't like your 'vert. I'm only saying if you're concerned about 0-60 as you stated in the OP, you probably driving the wrong car. I was saying it tongue-in-cheek of course. It's unfortunate the 'vert takes such a weight penalty. I also have a BMW vert, however it's not my M3. So I can enjoy top down driving as well.

[swamp2]

Originally Posted by Sticky

If you mash it too hard traction control will cut in and the car will cut power. It is based on the traction the tires have available.

Exactly the point and exactly what you want if traction is poor. However, I think wheel spin is managed by the brakes not by cutting power. Either way if the adjustment can be made very quickly, which it seems it can, it shouldn't matter. What good does NOT managing wheel spin do when poor or inadequate traction exists? Maybe you think endlessly spining/smoking your tires with a very high slip rate is the fastest way to accelerate? It absolutely isn't. IMO and in the opinion of multiple journalists MDM is the quickest way to get the car off the line and LC uses MDM.

[Sticky]

Originally Posted by swamp2

Exactly the point and exactly what you want if traction is poor. However, I think wheel spin is managed by the brakes not by cutting power. Either way if the adjustment can be made very quickly, which it seems it can, it shouldn't matter. What good does NOT managing wheel spin do when poor or inadequate traction exists? Maybe you think endlessly spining/smoking your tires with a very high slip rate is the fastest way to accelerate? It absolutely isn't. IMO and in the opinion of multiple journalists MDM is the quickest way to get the car off the line and LC uses MDM.

LC is the quickest way to get the car off the line, but it still can't do miracles. Using it in the wet for example won't work out.

When I would mash the gas, the traction control light would flicker and I did not feel brakes but the car cutting acceleration.

If traction is poor, MDM works great but the amount of throttle application plays a factor. A combination of both is ideal.

[footie]

Though not 100% certain, I thought TC + ABS = DSC, so that means traction control and braking are separate things to control a slide. I think sticky is correct and TC is power cut and not the brakes.

Anyway I know that LC is pretty useless in wet/slippy conditions, I tried the bloody thing and I am quicker when controlling the wheel spin myself. Though I am still under the opinion that is optimum conditions LC is best.

[96OCTNE]

Originally Posted by swamp2

Exactly the point and exactly what you want if traction is poor. However, I think wheel spin is managed by the brakes not by cutting power. Either way if the adjustment can be made very quickly, which it seems it can, it shouldn't matter. What good does NOT managing wheel spin do when poor or inadequate traction exists? Maybe you think endlessly spining/smoking your tires with a very high slip rate is the fastest way to accelerate? It absolutely isn't. IMO and in the opinion of multiple journalists MDM is the quickest way to get the car off the line and LC uses MDM.

Not saying your wrong swamp, just trying to understand. Your last sentence says LC uses MDM, I thought the settings were DSC, MDM, and no DSC. Doesn't LC use "no DSC"? I might be wrong, I'm also looking for the best launch outside of LC.

[skierman64]

The way I understand it, is that LC moderates the clutch engagement in order to control wheel spin. I don't believe that DSC or MDM are involved. ie, no rear braking and no throttle reductions occur on a LC start.

[Ronin13]

I believe that while the torque curve is flat, the motor really isn't in the sweet spot in the lower RPMs. So, I would expect that "some" wheelspin or clutch slippage is a good thing for this car right off the line so that the revs can build into the powerband without having the car bog.

[swamp2]

Originally Posted by 96OCTNE

Not saying your wrong swamp, just trying to understand. Your last sentence says LC uses MDM, I thought the settings were DSC, MDM, and no DSC. Doesn't LC use "no DSC"? I might be wrong, I'm also looking for the best launch outside of LC.

To engage LC you must turn DSC off. However, when using LC the car manages traction for you on takeoff which is normally the function of the DCS system. When you have DCS set to MDM wheelspin is minimized on launch and even though with LC DSC is technically off, it is much like DSC is in MDM. However, shifts from 2-3 and subsequent shifts do feel like DSC is off. It seems to manage the actual launch and the 1->2 shift only.

[footie]

I know this is off topic but it's interesting all the same.

I tried the M3 to the same point I test all of my cars and even though traction was a major problem and had to short shift from 1st to 2nd at less than 5K rpm, the car managed to be 12mph quicker than the S5.