Page 1 of 5 123 ... LastLast
Results 1 to 10 of 46

Thread: SQ5 (ZF 8 Speed) launch control

  1. #1

    Question SQ5 (ZF 8 Speed) launch control

    Hi

    I've been away from the forum for a bit, but I picked up my SQ5 a couple of months ago and enjoying it immensely.


    One frustration I do have though is the relatively subdued initial take off from standstill... Whether it's turbo lag or conservative torque programming, the first few car lengths sometimes leaves you wanting, which usually results in more go pedal pressure, and subsequently after the turbo spools up, far more acceleration then you really wanted. It's not a deal-breaker, but I had hoped it would be a bit more aggressive from start. I drive in dynamic & S mode 90% of the time, except on highways, so thats not it...


    I have used a couple of light brake-torque launches to assist when fast take off was needed, and this helps a lot, but have concern for the torque convertor to go too hard...


    I've clocked past the break-in period now and was surprised to read that the SQ5 has a launch control program like I had on the previous s-tronic Q5, haven't tried it yet, but got me thinking about how technically this is achieved in the ZF8.


    There's a lot of opinion in various discussions that it is simply a ecu controlled brake-torque launch, but most of this is from ppl who evidently have never driven a ZF8, as can be determined from the term 'slush box' being applied to it and regurgitating old ideas as to why a dual clutch trans is better than a torque convertor auto.


    Considering the only times the torque conv isn't locked is initial take off from standstill in first gear (seems to lock after max boost reached) and at low revs in higher gears to reduce NVH, it technically operates in most conditions in a very similar clutch-clutch change operation.


    So in pondering the SQ5 launch control function, I wondered whether a clutch-drop launch was possibly the method implemented, either using one of the gearset clutch/brakes, or the torque convertor locking clutch itself?


    Sorry for the epic post, I find technical concepts such as these interesting and as considerable internet search revealed very little, I thought I might ask the collective wealth of knowledge here if anyone could shed light on the technical operation involved?


    Thanks
    Marc
    Last edited by marc_aus; July 3rd, 2014 at 01:04 AM.

  2. #2
    Join Date
    Aug 2011
    Location
    Sarajevo, BiH
    Posts
    173
    Thanked: 14

    Default

    Description how works Launch Control on SQ5/Q5 you will not find anywhere, simply this know only the Audi engineers and 99,5 % of users not interested



    Q5 2.0TFSI, Silver, S-tronic, Milano leather, B&O, AMI, Parking System Plus, 3 spoke paddle shift, Bi-xenon, 19" 5-arm polished
    Sorry for my English

  3. #3

    Default

    Launch Control is a hoot! It works well.

  4. #4

    Default

    spijun, where are you getting those screen shots from? Have you been able to find an online owners manual or something?

    I didnt think the SQ5 would have launch control due to it being a torque convertor auto, i thought only DSG equipped cars had it.

    I am guessing it loads the living crap out of the gearbox and puts a whole stack of stress on everything as opposed to the clutch drop of a DSG box

  5. #5

    Default

    Apparently there is a counter, and you lose warranty after 250 launches.

  6. #6

    Default

    Quote Originally Posted by spijun View Post
    Description how works Launch Control on SQ5/Q5 you will not find anywhere, simply this know only the Audi engineers and 99,5 % of users not interested
    Maybe i should try some other car forums too, as the ZF8 is finding itself in many different cars. The implementation would be decided by ZF engineers, not Audi engineers anyway...


    Quote Originally Posted by ido09s View Post
    spijun, where are you getting those screen shots from? Have you been able to find an online owners manual or something?

    I didnt think the SQ5 would have launch control due to it being a torque convertor auto, i thought only DSG equipped cars had it.

    I am guessing it loads the living crap out of the gearbox and puts a whole stack of stress on everything as opposed to the clutch drop of a DSG box
    I thought this too, but there is a user manual documented procedure so it is obviously safe, and as its ECU/TCU controlled this way it would cut power prior to any damage.

    I don't buy this idea that a DSG clutch dump launch is less stressful on the transmission than torque converter launch, if anything there probably more instantaneous transmission load/stress in a DSG/manual launch than brake/torque launch as in the latter the load is built up progressively right though the drive train to the wheels and launch is achieved by letting go of the brake pedal, whereas clutch dump there is no preload so all the kinetic energy in the revving engine is transmitted through transmission, drive-shafts, diffs & axles from 0Nm to max torque all within a few milliseconds...

    However, the torque converter in Brake/Torque launch would be working quite hard and the heat/pressure would be a risk which is why i wondered about the actual technical process... if you ever look into the inner workings of the ZF8hp (link) , you'll notice it is all clutches (and brakes) providing the gear-set coupling anyway, as well a big torque converter locking clutch at the input side... so in theory a clutch-dump style launch is possible.

    For those that have used it already (assuming you were able to concentrate on the mechanics playing out and not just giggling to yourself as 2t of metal is launched as a silly speed), did you get the feeling it was pushing through the torque converter before releasing the brake? Or is it more like the DSG launch which puts no power through the trans until you let go of the brake - then goes with a bang?

    Quote Originally Posted by radd View Post
    Apparently there is a counter, and you lose warranty after 250 launches.
    I have read this rumour too, but i think its probably BS, particularly here in Australia. If the feature/procedure is in the user manual, it would need to have this 250 limitation in print nearby or it wont fly past the Australian Consumer Law. I work in an industry that also sells products to consumers, and let me just say if you put a feature/performance measure in writing, you'd better be certain it will deliver exactly as written or its on you! It does mention that the LC puts load on the car, and this may lead to wear and tear (tyres/clutch etc) but this doesn't provide any warranty exemption.

    Incidentally, my user manual suggests the LC program only applies to S-tronic transmission, anyone see any different in theirs?

    Cheers
    Marc.
    Last edited by marc_aus; July 3rd, 2014 at 01:09 PM.

  7. #7
    Join Date
    Aug 2011
    Location
    Sarajevo, BiH
    Posts
    173
    Thanked: 14

    Default

    Quote Originally Posted by ido09s View Post
    spijun, where are you getting those screen shots from? Have you been able to find an online owners manual or something?

    I didnt think the SQ5 would have launch control due to it being a torque convertor auto, i thought only DSG equipped cars had it.

    I am guessing it loads the living crap out of the gearbox and puts a whole stack of stress on everything as opposed to the clutch drop of a DSG box
    This is the version ( Bord-book ) that is on the CD and can be installed on models with navigation.
    Of course it can be read in the computer but is designed for use in the car

    Launch control have all new model (with all kinds: multitronic ® / S tronic ® / tiptronic gearbox)

    Last edited by spijun; July 3rd, 2014 at 05:50 PM.
    Q5 2.0TFSI, Silver, S-tronic, Milano leather, B&O, AMI, Parking System Plus, 3 spoke paddle shift, Bi-xenon, 19" 5-arm polished
    Sorry for my English

  8. #8
    Join Date
    Aug 2011
    Location
    Sarajevo, BiH
    Posts
    173
    Thanked: 14

    Default

    Quote Originally Posted by radd View Post
    Apparently there is a counter, and you lose warranty after 250 launches.
    You must be kidding ???????

    I ask for the source of your information
    Q5 2.0TFSI, Silver, S-tronic, Milano leather, B&O, AMI, Parking System Plus, 3 spoke paddle shift, Bi-xenon, 19" 5-arm polished
    Sorry for my English

  9. #9
    Join Date
    Aug 2011
    Location
    Sarajevo, BiH
    Posts
    173
    Thanked: 14

    Default

    Quote Originally Posted by marc_aus View Post
    Maybe i should try some other car forums too, as the ZF8 is finding itself in many different cars. The implementation would be decided by ZF engineers, not Audi engineers anyway...
    To some extent what is right, but there are parts which a product of Audi and software that has made Audi for their needs

    Quote Originally Posted by marc_aus View Post
    Incidentally, my user manual suggests the LC program only applies to S-tronic transmission, anyone see any different in theirs?

    Cheers
    Marc.
    It is not true that only for S-tronic. It is true only if you have an old model of automatic 6-speed gearboxes MY2009-2011

    Audi Q5 Controls Automatic gearbox S tronic®, tiptronic
    or
    Audi A6/S6 Controls Automatic gearbox multitronic® / S tronic® / tiptronic gearbox
    Last edited by spijun; July 3rd, 2014 at 05:20 PM.
    Q5 2.0TFSI, Silver, S-tronic, Milano leather, B&O, AMI, Parking System Plus, 3 spoke paddle shift, Bi-xenon, 19" 5-arm polished
    Sorry for my English

  10. #10

    Default

    Quote Originally Posted by radd View Post
    Apparently there is a counter, and you lose warranty after 250 launches.
    LOL! Likely you will lose your licence before the warranty.

    Dingah

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •