Blowing hot air




Results 1 to 17 of 17

Thread: Blowing hot air

  1. #1
    Join Date
    Jun 2014
    Location
    Cape Town or Jansenville or missing...
    Age
    38
    Posts
    10,490
    Thanked: 3060

    Default Blowing hot air

    We’ve all heard the complaints about these small turbocharged engines using a lot more fuel than their spec sheets claims.

    My own experience reflects this, a 300km stint with a brand new turbocharged 2 cylinder 875cc Fiat Panda resulted in over 10L/100km from an engine claimed to deliver 4L/100km.
    In comparison, my little naturally aspirated 1L 3 cylinder VW up! which is similarly rated and delivers similar real world performance, refuses to use more than 6L/100km no matter what you do.

    I’ve had my suspicions that the reason for this is as much the way you drive as the design of the engine, but this video gives a very nice in depth yet easy to understand explanation.



    Kudos to people making videos like this, I find them highly informative and entertaining.

  2. #2
    Join Date
    Aug 2009
    Location
    Centurion, South Africa
    Age
    52
    Posts
    1,781
    Thanked: 303

    Default Re: Blowing hot air

    Huh?

    My 1.2 Polo TSI ave between 6.6 and 5.5 l/100km and my 1.0 TSI between 5.8 and 5.2 l/100 Km. (In Pta trafffic! Even less on the open road)
    Pieter
    Fortuner 4x4
    Echo 4

  3. #3
    Join Date
    Jun 2014
    Location
    Cape Town or Jansenville or missing...
    Age
    38
    Posts
    10,490
    Thanked: 3060

    Default Re: Blowing hot air

    Quote Originally Posted by PieterOos View Post
    Huh?

    My 1.2 Polo TSI ave between 6.6 and 5.5 l/100km and my 1.0 TSI between 5.8 and 5.2 l/100 Km. (In Pta trafffic! Even less on the open road)
    Have you watched the video?

    It explains very nicely why you might get good consumption if you drive conservatively, yet why it can shoot up drastically when you use all the performance.

  4. #4
    Join Date
    Jan 2007
    Location
    Cape Town
    Age
    41
    Posts
    1,366
    Thanked: 203

    Default Re: Blowing hot air

    My Amarok with its 2l TD starts to "suie" as soon as I need to get somewhere in a hurry. Add a surfski on the roof and a head-wind and it becomes quite noticeable. On my commute however, it is nice and well-behaved.

  5. #5
    Join Date
    Sep 2006
    Location
    Robertson/ Larissa, Greece
    Age
    54
    Posts
    4,236
    Thanked: 1502

    Default Re: Blowing hot air

    Quote Originally Posted by JohanSlabbert View Post
    We’ve all heard the complaints about these small turbocharged engines using a lot more fuel than their spec sheets claims.

    My own experience reflects this, a 300km stint with a brand new turbocharged 2 cylinder 875cc Fiat Panda resulted in over 10L/100km from an engine claimed to deliver 4L/100km.
    In comparison, my little naturally aspirated 1L 3 cylinder VW up! which is similarly rated and delivers similar real world performance, refuses to use more than 6L/100km no matter what you do.
    In the same vain. My 4.5EFI Land Cruiser gave 6.2 km/l no matter how I drove!
    I guess the same principles apply.
    We can't change the wind but we can set our sails

  6. The Following 3 Users Say Thank You to Francois Theron For This Useful Post:


  7. #6
    Join Date
    Jun 2014
    Location
    Cape Town or Jansenville or missing...
    Age
    38
    Posts
    10,490
    Thanked: 3060

    Default Re: Blowing hot air

    Quote Originally Posted by Francois Theron View Post
    In the same vain. My 4.5EFI Land Cruiser gave 6.2 km/l no matter how I drove!
    I guess the same principles apply.
    I think you’ll find you’re not far off with that theory. My TJ was the same.

  8. #7
    Join Date
    Dec 2011
    Location
    East London
    Age
    34
    Posts
    16,418
    Thanked: 1827

    Default Re: Blowing hot air

    That's why VW developed stratified injection (FSI) in conjunction with Bosch.

    Ie, direct injection allows leaner burns without knock issues. Controlled burn.

    Read up on it. Great technology!

  9. The Following User Says Thank You to MariusFourie For This Useful Post:


  10. #8
    Join Date
    Aug 2009
    Location
    Centurion, South Africa
    Age
    52
    Posts
    1,781
    Thanked: 303

    Default Re: Blowing hot air

    If a turbo is 'on boost' consumption will go up and it is not limited to small cap engines. (It is physics, fuel : air (>>) etc.)
    Pieter
    Fortuner 4x4
    Echo 4

  11. #9
    Join Date
    Aug 2017
    Location
    Centurion
    Posts
    623
    Thanked: 447

    Default Re: Blowing hot air

    So what the video is showing is that you cannot have high levels of efficiency and high levels of performance at the same time - nothing new. The interplay between these depends on engine technology.

  12. #10
    Join Date
    Aug 2009
    Location
    Centurion, South Africa
    Age
    52
    Posts
    1,781
    Thanked: 303

    Default Re: Blowing hot air

    Quote Originally Posted by MariusFourie View Post
    Great technology!
    Uhm ja, debatable (In theory yes, but in the real world?)

    (Had an Audi 2.0 TFSI & still own a Golf 2.0 FSI, so I have the T-shirts. I am also not convinced that a catch can is the ultimate solution. Wasn't DI technology primarily developed to meet emission req's?)
    Last edited by PieterOos; 2018/08/02 at 03:12 PM.
    Pieter
    Fortuner 4x4
    Echo 4

  13. #11
    Join Date
    Feb 2016
    Location
    Paarl
    Age
    43
    Posts
    877
    Thanked: 354

    Default Re: Blowing hot air

    Quote Originally Posted by PieterOos View Post
    Uhm ja, debatable (In theory yes, but in the real world?)

    (Had an Audi 2.0 TFSI & still own a Golf 2.0 FSI, so I have the T-shirts. I am also not convinced that a catch can is the ultimate solution. Wasn't DI technology primarily developed to meet emission req's?)
    2SO?....Runs and hides...
    1996 Discovery 1 (SOLD)
    2009 Corsa Utility 1.7Dti (Everyday drive)
    2001 Mercedes C180 (Soon to be my eldest's car)
    2010 Kia Sedona 2.9Crdi (SWAMBO's ride)

  14. #12
    Join Date
    Aug 2009
    Location
    Centurion, South Africa
    Age
    52
    Posts
    1,781
    Thanked: 303

    Default Re: Blowing hot air

    Quote Originally Posted by Nitebob View Post
    2SO?....Runs and hides...
    Don't need to - you can stay and debate, how will it reach the top of the valves? (As it is a 'vapour' thing)
    Last edited by PieterOos; 2018/08/02 at 03:28 PM.
    Pieter
    Fortuner 4x4
    Echo 4

  15. #13
    Join Date
    Jun 2014
    Location
    Cape Town or Jansenville or missing...
    Age
    38
    Posts
    10,490
    Thanked: 3060

    Default Re: Blowing hot air

    Quote Originally Posted by SAND View Post
    So what the video is showing is that you cannot have high levels of efficiency and high levels of performance at the same time - nothing new. The interplay between these depends on engine technology.
    Except you can. But not in your average turbo petrol engine.

    If you watch carefully you'll see how he explains that on these small turbo engines, when you out foot, efficiency takes a nosedive as the mixture is enriched way past the optimum point to control knock, whereas an NA motor will be able to stay closer to the most efficient mixture and thereby deliver similar power with lower fuel consumption.
    Last edited by Johan Slabbert; 2018/08/02 at 03:59 PM.

  16. #14
    Join Date
    Jun 2014
    Location
    Cape Town or Jansenville or missing...
    Age
    38
    Posts
    10,490
    Thanked: 3060

    Default Re: Blowing hot air

    Quote Originally Posted by MariusFourie View Post
    That's why VW developed stratified injection (FSI) in conjunction with Bosch.

    Ie, direct injection allows leaner burns without knock issues. Controlled burn.

    Read up on it. Great technology!
    Dirty valves are a real issue...

    Quote Originally Posted by PieterOos View Post
    If a turbo is 'on boost' consumption will go up and it is not limited to small cap engines. (It is physics, fuel : air (>>) etc.)
    I think you'll see the video is more about efficiency than outright consumption. I think the way the guy explained a complex, multidimensional issue is very elegant.

    Quote Originally Posted by PieterOos View Post
    Uhm ja, debatable (In theory yes, but in the real world?)

    (Had an Audi 2.0 TFSI & still own a Golf 2.0 FSI, so I have the T-shirts. I am also not convinced that a catch can is the ultimate solution. Wasn't DI technology primarily developed to meet emission req's?)
    Curiously, some motors employs both direct and indirect injection, like the V6 in my Lexus IS250 of a decade ago. There are more benefits to this than just keeping the valves clean too.

    Quote Originally Posted by Nitebob View Post
    2SO?....Runs and hides...
    Quote Originally Posted by PieterOos View Post
    Don't need to - you can stay and debate, how will it reach the top of the valves? (As it is a 'vapour' thing)
    Exactly

  17. #15
    Join Date
    Jun 2012
    Location
    Benoni
    Age
    43
    Posts
    805
    Thanked: 401

    Default Re: Blowing hot air

    It all depends on your commute and driving style.

    At full taps a turbo charged engine consumes more fuel than a comparatively powerful NA engine. So if you spend a fair amount of time driving the car relatively hard then yes it will be heavier on fuel than a NA engine. But at small throttle opening it will use less fuel and as a whole the engine should be lighter. There is a crossover point where the small capacity turbo motor is more efficient than the NA motor.
    2012 Q7 4.2 TDI
    Birkin SR20VET race car


  18. #16
    Join Date
    Dec 2011
    Location
    East London
    Age
    34
    Posts
    16,418
    Thanked: 1827

    Default Re: Blowing hot air

    Even with turbo diesels.

    My R5 easily does sub 9.0L/100 when driven sedately.

    Be hasty and it does closer to 13L/100km

  19. #17
    Join Date
    Jan 2015
    Location
    Vredenburg
    Age
    40
    Posts
    2,157
    Thanked: 606

    Default Re: Blowing hot air

    Quote Originally Posted by Nitebob View Post
    2SO?....Runs and hides...
    LoL

Bookmarks

Posting Permissions

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