1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Why the bad 0-100MPh time for 2.0TDi?

Discussion in 'A3/S3/Sportback (8P Chassis)' started by SideShowBob, Nov 21, 2005.

  1. miketweed
    Offline

    miketweed Member

    Joined:
    Dec 21, 2004
    Messages:
    371
    Likes Received:
    0
    [Nov 22, 2005]
    Sorry to go off thread......

    Mike P - you're at Revo Daventry?

    I've just come off the phone with Doug at Revo (he said they were just finishing some DSG testing - must be yours!), I'm booked in tomorrow lunchtime for a remap on my 2.0T FSI DSG. I gather it is being released tomorrow to dealers around the UK.

    Not sure what their final figures are for the FSI T, (last I heard it was 260BHP+ and 300lbft+) can't wait to find out though!!
    #41
  2. SideShowBob
    Offline

    SideShowBob Member

    Joined:
    Dec 13, 2003
    Messages:
    36
    Likes Received:
    0
    [Nov 22, 2005]
    Well if a remap allows genuine sub 20 second to 100MPh to be possible, then its a pretty inexpensive and simple way of making a really nice luxury hatch into a warm/hot hatch.

    Ive heard fuel consumption on the 2.0TDi actually improves following the remap? is that genuine?
    #42
  3. Amchlolor
    Offline

    Amchlolor Active Member

    Joined:
    Jan 13, 2005
    Messages:
    5,604
    Likes Received:
    3
    [Nov 22, 2005]
    [ QUOTE ]
    Well if a remap allows genuine sub 20 second to 100MPh to be possible, then its a pretty inexpensive and simple way of making a really nice luxury hatch into a warm/hot hatch.

    Ive heard fuel consumption on the 2.0TDi actually improves following the remap? is that genuine?

    [/ QUOTE ]

    I'm not saying that you have forgotten,but some people tend to forget to add in the cost of their insurance loading.

    Okay,a remap might be £400,but it might cost you that again when you inform your insurance.

    If you bother of course...cough...
    #43
  4. marriedblonde
    Offline

    marriedblonde Moderator

    Joined:
    Dec 6, 2004
    Messages:
    4,371
    Likes Received:
    5
    [Nov 22, 2005]
    [ QUOTE ]
    Don't forget (as Bowfer has already said) speedo inaccuaracy - mine is running 10% optimistic, so unless you have satnav test for 0-110.

    [/ QUOTE ]

    In that case get your car looked at as you have a problem... Sure your tyres aren't flat as that would probably do it.

    According to GPS mines about 3 perhaps 4mph out at motorway speeds, my motorway speeds.

    J.
    #44
  5. mikep
    Offline

    mikep Member

    Joined:
    Jun 9, 2003
    Messages:
    591
    Likes Received:
    1
    [Nov 22, 2005]
    [ QUOTE ]
    Sorry to go off thread......

    Mike P - you're at Revo Daventry?

    I've just come off the phone with Doug at Revo (he said they were just finishing some DSG testing - must be yours!), I'm booked in tomorrow lunchtime for a remap on my 2.0T FSI DSG. I gather it is being released tomorrow to dealers around the UK.

    Not sure what their final figures are for the FSI T, (last I heard it was 260BHP+ and 300lbft+) can't wait to find out though!!

    [/ QUOTE ]

    Yup I was at Revo Daventry today, just got back I'll post the figures later on.

    The figures you quote for the TFsi are about right.
    #45
  6. mikep
    Offline

    mikep Member

    Joined:
    Jun 9, 2003
    Messages:
    591
    Likes Received:
    1
    [Nov 22, 2005]
    [ QUOTE ]
    [ QUOTE ]
    Well if a remap allows genuine sub 20 second to 100MPh to be possible, then its a pretty inexpensive and simple way of making a really nice luxury hatch into a warm/hot hatch.

    Ive heard fuel consumption on the 2.0TDi actually improves following the remap? is that genuine?

    [/ QUOTE ]

    I'm not saying that you have forgotten,but some people tend to forget to add in the cost of their insurance loading.

    Okay,a remap might be £400,but it might cost you that again when you inform your insurance.

    If you bother of course...cough...

    [/ QUOTE ]

    S'funny my insurance increase was £50. But I am ancient!
    #46
  7. marriedblonde
    Offline

    marriedblonde Moderator

    Joined:
    Dec 6, 2004
    Messages:
    4,371
    Likes Received:
    5
    [Nov 22, 2005]

    So whats the drive like Mike? Details, details details... Oh and how much for a fellow AS member /ubbthreads/images/graemlins/laugh.gif
    #47
  8. powerplay
    Offline

    powerplay Grrrr

    Joined:
    Aug 27, 2005
    Messages:
    182
    Likes Received:
    0
    [Nov 22, 2005]
    [ QUOTE ]
    Don't forget (as Bowfer has already said) speedo inaccuaracy - mine is running 10% optimistic, so unless you have satnav test for 0-110.

    [/ QUOTE ]

    10% sounds like an auful lot. Generally speedometers are about 3-5% optimistic at slow speeds, but should be pretty accurate over about 70.

    I have a roadangel fitted in mine and at "true" constant 30mph it reads about 32-33mph, at true 50 it reads 52 and at true 100 it reads as near as I can tell bang on 100.
    #48
  9. porkapig
    Offline

    porkapig New Member

    Joined:
    Jul 28, 2005
    Messages:
    22
    Likes Received:
    0
    [Nov 22, 2005]
    my speedos 10% out as well when i compare it to the gps.
    #49
  10. Dandle
    Offline

    Dandle Member

    Joined:
    Aug 26, 2005
    Messages:
    852
    Likes Received:
    1
    [Nov 22, 2005]
    I believe its UK law that manufacturers have to include a speedo error on there cars to take into account wrong tyre pressure and the like that can cause inaccuracies. I don't think the error has to be 10% though, this would seem a little high. My Volvo is about 3mph slower than indicated betwen 30 and 80mph and the error gets bigger over 80mph but not by much.
    #50
  11. scoulbeck
    Offline

    scoulbeck New Member

    Joined:
    Jan 25, 2005
    Messages:
    14
    Likes Received:
    0
    [Nov 22, 2005]
    Mike P who is your insurer please?

    Si
    #51
  12. Karcsi
    Offline

    Karcsi Member

    Joined:
    Mar 6, 2003
    Messages:
    426
    Likes Received:
    0
    [Nov 23, 2005]
    [ QUOTE ]


    I was right yesterday,it's the change from 3rd to 4th,at just about bang on 60mph,that absolutely kills the acceleration.
    The car takes a comparitive age to pick up from that gearchange.



    [/ QUOTE ]

    That still happens in my remapped car. So I don't change up at 60, but nearer 70 (when I really want to move). No problems there. Although, with the remap mine pulls strongly almost all the way to the red line. Wasn't so as standard.
    #52
  13. bunny
    Offline

    bunny Member

    Joined:
    Aug 5, 2005
    Messages:
    102
    Likes Received:
    0
    [Nov 23, 2005]
    At exactly 77mph my car reads 85 on the speedo. Maybe it varies from car to car, but the 2 other A3's at work are exactly the same, but my old MK4 Golf was worryingly accurate... worrying because I always thought 80 - 85 on the clock would be well below the 77 "limit".
    #53
  14. cosmicblue
    Offline

    cosmicblue Member

    Joined:
    Sep 16, 2005
    Messages:
    320
    Likes Received:
    0
    [Nov 23, 2005]
    [ QUOTE ]
    All good info about this, and as no one would buy a 2l diesel because they want performance, I suppose a slow 0-100MHp time isnt particullaly important.

    [/ QUOTE ]

    Having lived with my Tdi for a couple of weeks, I'd suggest that for legal fun the Tdi is outrageous.

    100mph is academic these days as it is instant ban territory. For quick cross country driving, in the real world (with speed cameras everywhere) the Tdi with or without DSG would be hard to beat - the wicked grunt coming out of slow corners is very addictive.
    #54
  15. h5djr
    Offline

    h5djr Well-Known Member VCDS Map User

    Joined:
    Jan 23, 2003
    Messages:
    8,030
    Likes Received:
    799
    [Nov 23, 2005]
    Speedometers are allowed to be -10% +0% according to the regulations so most manufacters err on the low side to ensure they do not exceed the +0% figure.

    Compared with my GPS readout my speedo reads abount 9% under.
    #55
  16. SideShowBob
    Offline

    SideShowBob Member

    Joined:
    Dec 13, 2003
    Messages:
    36
    Likes Received:
    0
    [Nov 23, 2005]
    [ QUOTE ]
    Having lived with my Tdi for a couple of weeks, I'd suggest that for legal fun the Tdi is outrageous.

    100mph is academic these days as it is instant ban territory. For quick cross country driving, in the real world (with speed cameras everywhere) the Tdi with or without DSG would be hard to beat - the wicked grunt coming out of slow corners is very addictive.

    [/ QUOTE ]

    Thats the whole point really, so many cars have brilliant on paper figures that are only applicable if you drive them exclusively on a empty race track, as opposed to on the typical British roads we all really drive on.

    Thats why it was simply curiosity, the car (in the test drive) had excellent power delivery for the varied driving I did in it, which is where a car shows its true useful qualities.
    #56
  17. Amchlolor
    Offline

    Amchlolor Active Member

    Joined:
    Jan 13, 2005
    Messages:
    5,604
    Likes Received:
    3
    [Nov 23, 2005]
    [ QUOTE ]
    So I don't change up at 60, but nearer 70 (when I really want to move).

    [/ QUOTE ]

    I'm assuming you don't have DSG.
    We don't have that option.

    /ubbthreads/images/graemlins/thumbsdown.gif
    #57
  18. mikep
    Offline

    mikep Member

    Joined:
    Jun 9, 2003
    Messages:
    591
    Likes Received:
    1
    [Nov 23, 2005]
    I use Direct Line, and have used Adrian Flux in the past as well both pretty good.
    #58
  19. Karcsi
    Offline

    Karcsi Member

    Joined:
    Mar 6, 2003
    Messages:
    426
    Likes Received:
    0
    [Nov 23, 2005]
    [ QUOTE ]
    Speedometers are allowed to be -10% +0% according to the regulations so most manufacters err on the low side to ensure they do not exceed the +0% figure.

    Compared with my GPS readout my speedo reads abount 9% under.

    [/ QUOTE ]

    Don't you have that the wrong way around? It is illegal for a speedo to read under, and anything more than 10% over.


    Yes, Bowfer, I have a manual /ubbthreads/images/graemlins/woohoo.gif. Doesn't sport mode allow you to use more of the rev range?
    #59
  20. Dandle
    Offline

    Dandle Member

    Joined:
    Aug 26, 2005
    Messages:
    852
    Likes Received:
    1
    [Nov 23, 2005]
    No they have to under read by law.
    #60
  21. Amchlolor
    Offline

    Amchlolor Active Member

    Joined:
    Jan 13, 2005
    Messages:
    5,604
    Likes Received:
    3
    [Nov 23, 2005]
    [ QUOTE ]
    Yes, Bowfer, I have a manual /ubbthreads/images/graemlins/woohoo.gif. Doesn't sport mode allow you to use more of the rev range?

    [/ QUOTE ]

    Nope,it doesn't matter what mode you're in,the 'top-end' gearchange point is the same.

    Very very annoying as my car is still pulling very strongly when it changes up.

    If it was breathless by the change up point I wouldn't mind so much,as I don't rev cars for the sake of revving them,but when it's still pulling very strongly I feel I'm being robbed.

    The manual box is geared slightly taller in third as well remember,so even if the DSG didn't 'take over' it's debatable it would get to 70mph in third.

    Maybe 65-ish or something.
    Still,any little extra in third would help when changing to fourth.
    #61
  22. imported_jimbogrey
    Online

    imported_jimbogrey Guest

    [Nov 23, 2005]
    No!!!! if they read under you would be going faster than indicated!!!!
    #62
  23. SideShowBob
    Offline

    SideShowBob Member

    Joined:
    Dec 13, 2003
    Messages:
    36
    Likes Received:
    0
    [Nov 23, 2005]
    Yeah, they must over read, so you think you're going faster than you actually are.
    #63
  24. Karcsi
    Offline

    Karcsi Member

    Joined:
    Mar 6, 2003
    Messages:
    426
    Likes Received:
    0
    [Nov 23, 2005]
    #64
  25. marriedblonde
    Offline

    marriedblonde Moderator

    Joined:
    Dec 6, 2004
    Messages:
    4,371
    Likes Received:
    5
    [Nov 23, 2005]
    #65
  26. h5djr
    Offline

    h5djr Well-Known Member VCDS Map User

    Joined:
    Jan 23, 2003
    Messages:
    8,030
    Likes Received:
    799
    [Nov 23, 2005]
    The following is a post I put up on 12 April 2005...

    I have looked further into the question of the accuracy of speedometers and found the following in the ACPO Guidelines on speeding, and the UK law regarding prosecution.
    Vehicle construction and use regulations require a vehicle speedometer accuracy to be in the range of -0% to +10%. The implications are that it must never under-read - for obvious reasons - but may over-read. As the cost of manufacturing a speedometer with -0% error would be very costly they all over-read by a few percent without exception. Even if speed is measured correctly the display may not be accurate, so a speedometer error is allowed. Because of this, the Association of Chief Police Officers (ACPO) have an official formula for calculating a speeding offence. It allows a leeway of 10% plus 2mph.
    #66
  27. porkapig
    Offline

    porkapig New Member

    Joined:
    Jul 28, 2005
    Messages:
    22
    Likes Received:
    0
    [Nov 23, 2005]
    intersting to see over on the cuprasport forum revo are saying >200bhp is possible from a 140tdi - but thats where injectors and turbos are just about at their max - so de tunning is anticipated.

    i'm definately interested in a remap providing its switchable back to normal via the diagnostics port

    any idea what sort of cost its looking like?
    #67
  28. Karcsi
    Offline

    Karcsi Member

    Joined:
    Mar 6, 2003
    Messages:
    426
    Likes Received:
    0
    [Nov 23, 2005]
    [ QUOTE ]
    Because of this, the Association of Chief Police Officers (ACPO) have an official formula for calculating a speeding offence. It allows a leeway of 10% plus 2mph.

    [/ QUOTE ]

    Came across this as I was searching. I don't get it. If a speedo over reads, why do the police have to compensate by allowing you to break the speed limit by 10 and 2? If you are actually travelling at 79mph, say, your speedo could read as much as 89mph. The police would only need to compensate if speedos were allowed to under read, surely? OK, perhaps they are referring to a police car using it's own speedo as the benchmark when judging if someone is speeding (assuming theirs is calibrating as badly as ours). But that's sod all to do with any bespoke speed measuing device, no?
    #68
  29. mikep
    Offline

    mikep Member

    Joined:
    Jun 9, 2003
    Messages:
    591
    Likes Received:
    1
    [Nov 23, 2005]
    [ QUOTE ]
    intersting to see over on the cuprasport forum revo are saying >200bhp is possible from a 140tdi - but thats where injectors and turbos are just about at their max - so de tunning is anticipated.

    i'm definately interested in a remap providing its switchable back to normal via the diagnostics port

    any idea what sort of cost its looking like?

    [/ QUOTE ]

    It's £499 + vat.
    #69
  30. AndyMac
    Offline

    AndyMac Moderator Staff Member Moderator

    Joined:
    Jun 10, 2003
    Messages:
    9,833
    Likes Received:
    35
    [Nov 23, 2005]
    Over read is actually the correct term but I think we know what you mean, 40mph on speedo is actually 36mph etc etc
    #70
  31. bunny
    Offline

    bunny Member

    Joined:
    Aug 5, 2005
    Messages:
    102
    Likes Received:
    0
    [Nov 23, 2005]
    [ QUOTE ]


    Came across this as I was searching. I don't get it. If a speedo over reads, why do the police have to compensate by allowing you to break the speed limit by 10 and 2? If you are actually travelling at 79mph, say, your speedo could read as much as 89mph. The police would only need to compensate if speedos were allowed to under read, surely?

    [/ QUOTE ]

    An excellent point Karsci - to paraphrase your point;

    "If the law says we can only do 70mph then we should all drive at what appears to be 70mph on our speedos.

    Then the extra leeway allowed would only make sense if a speedo under-read."


    However I think the law is there to take account of the fact that speedo inaccuracies are not only public knowledge, but are actually deliberately engineered into a vehicle.

    Think of the lawsuits in the US if someone crashing at an actual 58mph had thought they were only doing 55mph - no doubt a US court would agree that the 3mph difference was crucial.

    Given that there will always be some degree of error, it is safer for a manufacturer to err on the side of caution and make sure that any car that shows 55mph will be doing 55mph at the very most.
    #71
  32. AndyMac
    Offline

    AndyMac Moderator Staff Member Moderator

    Joined:
    Jun 10, 2003
    Messages:
    9,833
    Likes Received:
    35
    [Nov 24, 2005]
    It used to be for speedo error back when speedo's were purely a rough guide to actual speed. Now it's more to do with human error as we do occasionally have to glance up from the speedo to see where we're going. Having said that many forces have tried zero tolerance with some great results for their coffers.
    #72
  33. Karcsi
    Offline

    Karcsi Member

    Joined:
    Mar 6, 2003
    Messages:
    426
    Likes Received:
    0
    [Nov 24, 2005]
    [ QUOTE ]


    An excellent point Karsci - to paraphrase your point;

    "If the law says we can only do 70mph then we should all drive at what appears to be 70mph on our speedos.

    Then the extra leeway allowed would only make sense if a speedo under-read."


    However I think the law is there to take account of the fact that speedo inaccuracies are not only public knowledge, but are actually deliberately engineered into a vehicle.

    Think of the lawsuits in the US if someone crashing at an actual 58mph had thought they were only doing 55mph - no doubt a US court would agree that the 3mph difference was crucial.

    Given that there will always be some degree of error, it is safer for a manufacturer to err on the side of caution and make sure that any car that shows 55mph will be doing 55mph at the very most.

    [/ QUOTE ]

    I wasn't commenting on the law, but the Police's policy to compensate for something that does not need to be compensated. The only way this works is if everyone assumed that their speedo did over read by 10% + 2, and then drove accordingly. You could be wrong, the speedo actually being quite accurate, and thus be over the limit by a similar margin. However, you shouldn't assume, therefore the Police policy is an arse.

    Having said that, Andy's probably got the answer - it's just leniency from the Police, because you cannot be speedo-watching all the time. But wouldn't it make more sense that a 30 limit meant 30, and then the fines and penalties were graded from a small fine through to imprisonment?

    May be it was introduced as an administation limit - cost more to enforce that the benefits (mainly financial, me thinks cynically). But these days it would cost next to nothing to enforce.
    #73
  34. miketweed
    Offline

    miketweed Member

    Joined:
    Dec 21, 2004
    Messages:
    371
    Likes Received:
    0
    [Nov 24, 2005]
    Speedos must under-read? what are you talking about???

    That legal extract says:

    "The requirements are also that the indicated speed must never be less than the true speed."

    Car speedos have to over-read is correct!!

    With any electro-mechanical instrument of this nature, the error is specified as a % of full scale deflection (FSD), The largest errors are always at the top of any scale with less errors the lower down you go! (not vice versa as suggested by others)

    EXAMPLE: If your speedo reads to 150mph and is calibrated to +5% FSD +10mph (figures given in the legal extract previously), that means it will have a maximum error of +7.5mph +10mph at an indicated 150mph.

    i.e. it could read 150 when your doing at least 132.5 (more likely somewhere in between, but never less)

    Don't forget the general '+10mph' figure can occur anywhere in the range, so your speedo could read 10mph when you were stationary and it would still be legal and in tolerance!!

    When checked against Road Angel, mine is spot on upto 40mph, then starts to shift. (tested on a track)

    70 on GPS = 74 on clock

    100 on GPS = 107 on clock

    120 on GPS = 129 on clock

    Even the difference in pressure from cold to hot (3 or 4 PSI?) make 1 or 2 mph difference at 70mph.
    #74
  35. Karcsi
    Offline

    Karcsi Member

    Joined:
    Mar 6, 2003
    Messages:
    426
    Likes Received:
    0
    [Nov 24, 2005]
    Nice one Miket.

    Now, another question is what affect this has on the odometer reading? I assume that your speed and distance meters are based on the same information relayed from the spinning wheels. So if it is over reading your speed by up to 10%, then does it mean your odometer is showing your mileage at 10% more than reality?
    #75
  36. bunny
    Offline

    bunny Member

    Joined:
    Aug 5, 2005
    Messages:
    102
    Likes Received:
    0
    [Nov 24, 2005]
    [ QUOTE ]
    Speedos must under-read? what are you talking about???


    [/ QUOTE ]

    Read again Mike - I don't think anyone here said speedos must under-read.
    #76
  37. miketweed
    Offline

    miketweed Member

    Joined:
    Dec 21, 2004
    Messages:
    371
    Likes Received:
    0
    [Nov 24, 2005]
    Absolutely.

    Also your MPG is out and your services are coming up to soon. Not to mention the depreciation!

    I've done 24,300 miles since new in early March. Or maybe thats 21,870? ;-)

    It's all relative I suppose. After all the tolerance applies to all vehicles.
    #77
  38. miketweed
    Offline

    miketweed Member

    Joined:
    Dec 21, 2004
    Messages:
    371
    Likes Received:
    0
    [Nov 24, 2005]
    [ QUOTE ]
    Speedometers are allowed to be -10% +0% according to the regulations so most manufacters err on the low side to ensure they do not exceed the +0% figure.

    Compared with my GPS readout my speedo reads abount 9% under.

    [/ QUOTE ]

    There were a few who thought they should 'under' read.

    Or am I going mad?
    #78
  39. bunny
    Offline

    bunny Member

    Joined:
    Aug 5, 2005
    Messages:
    102
    Likes Received:
    0
    [Nov 24, 2005]
    [ QUOTE ]
    [ QUOTE ]
    Speedometers are allowed to be -10% +0% according to the regulations so most manufacters err on the low side to ensure they do not exceed the +0% figure.

    Compared with my GPS readout my speedo reads abount 9% under.

    [/ QUOTE ]

    There were a few who thought they should 'under' read.

    Or am I going mad?

    [/ QUOTE ]

    Errr sorry - I forgot about David's temporary brain fade...
    #79
  40. lister
    Offline

    lister New Member

    Joined:
    Oct 24, 2005
    Messages:
    13
    Likes Received:
    0
    [Nov 25, 2005]
    [ QUOTE ]

    I also believe that boost is cut in 1st gear in the tdi - mine is flat as anything in 1st but 2nd and beyond has 'full beans' - anyone else experience this?


    [/ QUOTE ]

    I also found this pretty noticeable - I remember reading something about "engine torque control" so I guess the boost is electronically controlled, no doubt to reduce first gear wear.
    #80

Share This Page