Best way to launch DMS'd 535d for timing runs?

[berry100]

What is best way to launch the 535d for some timing runs?

Did some crude stopwatch timings, and got 6.2 and 14.0 on the 60 and 100mph timings.....

wasn't very good on the launch at all, was trying it out in DS mode, would the manual mode be better or even standard D mode?

[m12_nathan]

Would've thought that holding the brake down, nailing the throttle and then coming off the brake would be fastest, not the kindest to the car but that is how journos launch auto cars IIRC.

[Cyclone1]

I ran my remapped 335D at Fighting Torque a few months ago, I found that the best times were recorded with the car in normal "D" mode and not "DS" or manual mode. The best launch was done at between 1200-1500rpm with your left foot on the brake pedal and right holding revs on the accelerator. I have since found that if you hold the brake and then rev from idle and release just as the needle hits 1500rpm then this also gives a rapid launch.

Jules.

[dannylt]

Sticky tarmac and pre-warmed rear tyres? With TC off you get lots of pointless wheelspin without an LSD, and with it on it cuts way too much power.

[Welshbeef]

berry100 said:

What is best way to launch the 535d for some timing runs?

Did some crude stopwatch timings, and got 6.2 and 14.0 on the 60 and 100mph timings.....

wasn't very good on the launch at all, was trying it out in DS mode, would the manual mode be better or even standard D mode?

Question why?

The left foot braking and building up the revs then releasing the brake is doing your car no end of good - is it your own car or a comp car (in which case youd not care about additional wear).

[Pentoman]

Does it really spin its wheels from a standing start in a straight line on dry smooth tarmac? Impressive, never driven an auto that does that, even a 5.0 325bhp Merc two seater and V8 & V12 Beemer saloons. Like the idea of it. When turning or pulling out at junctions yes, but straight dry road no.

[Cyclone1]

Welshbeef said:

berry100 said:

What is best way to launch the 535d for some timing runs?

Did some crude stopwatch timings, and got 6.2 and 14.0 on the 60 and 100mph timings.....

wasn't very good on the launch at all, was trying it out in DS mode, would the manual mode be better or even standard D mode?

Question why?

The left foot braking and building up the revs then releasing the brake is doing your car no end of good - is it your own car or a comp car (in which case youd not care about additional wear).

It does the car hardly any damage at all. 1500rpm is nothing, it's not like it is being held at 4000rpm then dumping the clutch like in some cars. Remember that this is also a very well built car with almost all mechanical wear and tear items specified well within max tolerance levels.

It is a fairly sporty high powered car, if people can't ask what the best way of launching it is then there is something wrong.........This is Pistonheads after all, a site where Car Enthusiasts like to discuss car related subjects and in most instances that covers performance related subjects. After all you don't buy a sporty or high powered car and drive it like it's made from cotton wool.

Jules.

Jules.

[wobert]

Cyclone1 said:

Welshbeef said:

berry100 said:

What is best way to launch the 535d for some timing runs?

Did some crude stopwatch timings, and got 6.2 and 14.0 on the 60 and 100mph timings.....

wasn't very good on the launch at all, was trying it out in DS mode, would the manual mode be better or even standard D mode?

Question why?

The left foot braking and building up the revs then releasing the brake is doing your car no end of good - is it your own car or a comp car (in which case youd not care about additional wear).

It does the car hardly any damage at all. 1500rpm is nothing, it's not like it is being held at 4000rpm then dumping the clutch like in some cars. Remember that this is also a very well built car with almost all mechanical wear and tear items specified well within max tolerance levels.

It is a fairly sporty high powered car, if people can't ask what the best way of launching it is then there is something wrong.........This is Pistonheads after all, a site where Car Enthusiasts like to discuss car related subjects and in most instances that covers performance related subjects. After all you don't buy a sporty or high powered car and drive it like it's made from cotton wool.

Jules.

Jules.

Not strictly correct.....

With a torque converter, stalling the converter against the brakes means all the energy from the engine is heating the oil in the converter up.

Do this for a prolonged time +30secs & you will start to burn the oil. This will then affect the performance / longevity of the clutches, bearings etc.

Stalling the converter for say 5secs is OK, just don't hold it on the brakes for too long.

Edited by wobert on Wednesday 7th November 20:07

[Cyclone1]

wobert said:

Cyclone1 said:

Welshbeef said:

berry100 said:

What is best way to launch the 535d for some timing runs?

Did some crude stopwatch timings, and got 6.2 and 14.0 on the 60 and 100mph timings.....

wasn't very good on the launch at all, was trying it out in DS mode, would the manual mode be better or even standard D mode?

Question why?

The left foot braking and building up the revs then releasing the brake is doing your car no end of good - is it your own car or a comp car (in which case youd not care about additional wear).

It does the car hardly any damage at all. 1500rpm is nothing, it's not like it is being held at 4000rpm then dumping the clutch like in some cars. Remember that this is also a very well built car with almost all mechanical wear and tear items specified well within max tolerance levels.

It is a fairly sporty high powered car, if people can't ask what the best way of launching it is then there is something wrong.........This is Pistonheads after all, a site where Car Enthusiasts like to discuss car related subjects and in most instances that covers performance related subjects. After all you don't buy a sporty or high powered car and drive it like it's made from cotton wool.

Jules.

Jules.

Not strictly correct.....

With a torque converter, stalling the converter against the brakes means all the energy from the engine is heating the oil in the converter up.

Do this for a prolonged time +30secs & you will start to burn the oil. This will then affect the performance / longevity of the clutches, bearings etc.

Stalling the converter for say 5secs is OK, just don't hold it on the brakes for too long.

Edited by wobert on Wednesday 7th November 20:07

Point taken. But for the *odd* launch (ie once in a blue moon and not every day) then it's hardly going to make that much difference. Plus I doubt whether anyone would hold it there for 30 seconds plus.

Jules.

[Aeroresh]

Ive found the best launch technique is to leave it in normal drive and just press the throttle!

Ive timed mine with GPS at 5.3 to 60 without trying too hard.

[berry100]

Thanks all, I'll have another bash when it's quiet......once I can manage sub 6 secs then I'll be a happy chap....am just trying to convince myself the car still has the DMS remap as it was serviced at BMW about 3 weeks ago by the previous owner and as I've not had one that is stock then am just checking the DMS remap hasn't been reflashed over...

[Silent1]

Cyclone1 said:

....It is a fairly sporty high powered car.....

A 535D is in no way 'sporty' it's a diesel saloon designed for mileage not b-lane blasts

As for someone elses comment on trashing the car/gearbox, i can't see how, all you're doing is spinning a 'fan' inside the torque converter whilst holding the other stationary, TBH i can't see it cause much if any more damage than just accelerating.

[Welshbeef]

Silent1 said:

Cyclone1 said:

....It is a fairly sporty high powered car.....

A 535D is in no way 'sporty' it's a diesel saloon designed for mileage not b-lane blasts

As for someone elses comment on trashing the car/gearbox, i can't see how, all you're doing is spinning a 'fan' inside the torque converter whilst holding the other stationary, TBH i can't see it cause much if any more damage than just accelerating.

To be frank Id say any 5 series even the M5 is not designed for narrow A & B roads - any artic/4x4 coming the other way when pushing on leave hardly any room, so unless the road is totally empty and you can guarentee it to stay that way then the 5 series is not suited to very fast A/B road fun.

[Cyclone1]

Silent1 said:

Cyclone1 said:

....It is a fairly sporty high powered car.....

A 535D is in no way 'sporty' it's a diesel saloon designed for mileage not b-lane blasts

As for someone elses comment on trashing the car/gearbox, i can't see how, all you're doing is spinning a 'fan' inside the torque converter whilst holding the other stationary, TBH i can't see it cause much if any more damage than just accelerating.

Read it again, I said "fairly sporty".......agreed it's no sports car but compared to an average saloon and in M Sport guise (more cosmetic than anything) then I stand by what I said in it being "fairly sporty". I used to drive an Audi S4 which most enthusiasts would have said at the time that it was a "Sports" saloon, but as good as it was I know that my current 335D would have the edge on it on the A and B roads that I frequently travel along.

Jules.

[Silent1]

Cyclone1 said:

Silent1 said:

Cyclone1 said:

....It is a fairly sporty high powered car.....

A 535D is in no way 'sporty' it's a diesel saloon designed for mileage not b-lane blasts

As for someone elses comment on trashing the car/gearbox, i can't see how, all you're doing is spinning a 'fan' inside the torque converter whilst holding the other stationary, TBH i can't see it cause much if any more damage than just accelerating.

Read it again, I said "fairly sporty".......agreed it's no sports car but compared to an average saloon and in M Sport guise (more cosmetic than anything) then I stand by what I said in it being "fairly sporty". I used to drive an Audi S4 which most enthusiasts would have said at the time that it was a "Sports" saloon, but as good as it was I know that my current 335D would have the edge on it on the A and B roads that I frequently travel along.

Jules.

Read it again, i didn't say sports car, i derided the fact you hinted at it being sporty. There's nothing sporty about it, yes it's agressive looking but it's not like the suspension/engine has been set up for anything else that A road / Motorways

[eliot]

Dont know about the newer 5's by the auto on my e39 always starts off in 2nd gear if left in D. In sport mode, is starts from 1st. I tried holding against the brakes once, it just bogs the engine down - I think the electronic throttle figures out whats going on and reigns things in.

[wobert]

eliot said:

Dont know about the newer 5's by the auto on my e39 always starts off in 2nd gear if left in D. In sport mode, is starts from 1st. I tried holding against the brakes once, it just bogs the engine down - I think the electronic throttle figures out whats going on and reigns things in.

The converter has a "stall" speed by design.

The stall speed is governed by the design of the converter itself, mainly by the form of the vanes on the iside on the converter housing and the impeller. By varying the angle of these vanes affects the flow of oil internally, and hence the characteristics of the converter.

There is also some "tuning" of the setup when specifying the match between converter & engine.

On a gasoline engine the stall speed will be around 2500 - 3000 rpm. On a diesel I would expect it to be on or around peak torque.

[eliot]

wobert said:

The converter has a "stall" speed by design.

The stall speed is governed by the design of the converter itself, mainly by the form of the vanes on the iside on the converter housing and the impeller. By varying the angle of these vanes affects the flow of oil internally, and hence the characteristics of the converter.

There is also some "tuning" of the setup when specifying the match between converter & engine.

On a gasoline engine the stall speed will be around 2500 - 3000 rpm. On a diesel I would expect it to be on or around peak torque.

Yes, Im familiar with stall speeds - I would very suprised if the stall on a production car is anything over 1800-2k rpm though.

[wobert]

eliot said:

wobert said:

The converter has a "stall" speed by design.

The stall speed is governed by the design of the converter itself, mainly by the form of the vanes on the iside on the converter housing and the impeller. By varying the angle of these vanes affects the flow of oil internally, and hence the characteristics of the converter.

There is also some "tuning" of the setup when specifying the match between converter & engine.

On a gasoline engine the stall speed will be around 2500 - 3000 rpm. On a diesel I would expect it to be on or around peak torque.

Yes, Im familiar with stall speeds - I would very suprised if the stall on a production car is anything over 1800-2k rpm though.

The last auto I drove (Rover 623 GSi) had a stall speed of 2700 rpm

[dannylt]

Silent1 said:

Read it again, i didn't say sports car, i derided the fact you hinted at it being sporty. There's nothing sporty about it, yes it's agressive looking but it's not like the suspension/engine has been set up for anything else that A road / Motorways

Why are you being so deliberately offensive? Clearly it's all subjective anyway, so I don't see why you need to deride it as you say. I certainly think it's more sporty than the majority of mass produced cars out there - and certainly faster than a lot of "sports cars". So do you have something constructive to say about launching one? I doubt it.