1. Introducing the smashing new Team FIAT T-Shirt !! To order yours click here : Team FIAT T-Shirt

The Layman's Perspective: So, why is every engine turbocharged nowadays?

Discussion in 'Technical' started by gurjinder, Aug 5, 2014.

  1. asimpleson

    asimpleson Esperto

    Messages:
    3,000
    Heptanesia
    Linea 1.3
    Uno 1.7 and Siena 1.7TD are same engine, the latter having a Garrett Turbocharger. You can always find online if older block/head or platform have been used. To state the obvious there is usually different ECU/Maps and upgraded pumps or injectors etc., coupled with host of other modifications to plumbing and exhausts, especially for factory rolled out turbo cars since designs are standardized and tested in labs, but you probably know that already. :)
    Vijairaj likes this.
  2. Jotinder

    Jotinder Regolare

    Messages:
    308
    New Delhi
    Linea 1.3
    Nice Information.
  3. Murphy_Fiat

    Murphy_Fiat Superiore

    Messages:
    648
    Trivandrum
    Trivandrum
    Linea T-Jet
    Thanks for sharing. Very informative.
  4. gurjinder

    gurjinder Staff Member Janitor

    Messages:
    3,989
    Punjab
    Happy to hear! :)
  5. Dilip patel

    Dilip patel Amatore

    Messages:
    190
    ahmedabad
    Yes I think 1.4 T jet have more FE then 1.4 Na
    prabhjot likes this.
  6. Dilip patel

    Dilip patel Amatore

    Messages:
    190
    ahmedabad
    Selection of good air filter effect on turbo charge engine.?
  7. swgaan

    swgaan Amatore

    Messages:
    231
    MH-46
    Panvel, Maharashtra
    Grande Punto 1.3
    nice peace of information Gurjinder.
  8. prabhjot

    prabhjot Esperto

    Messages:
    2,451
    delhi ncr
    Am I right in assuming: there can be no turbocharging without turbolag, especially pronounced on small displacement engines? Unless there is supercharging and/or the use of twin-turbos? And that if the turbo and the engine are tuned for less/no lag, they must necessarily giveup torque in higher gears, higher speeds, at higher but not too high rpm? clarification on the last point's validity or otherwise, please!

    thanks
  9. gurjinder

    gurjinder Staff Member Janitor

    Messages:
    3,989
    Punjab
    Hi,

    The old adage, "There is no such thing as free lunch" holds completely true for turbocharging a vehicle. Yes, it will give more power but the throttle response will not be as good and substantial power will not start coming on until some X rpm. As you say, especially on small displacement engines, turbo lag is hard to counter unless one goes for compound charging (using both supercharging and turbocharging) or utilising a combination of two or more turbos to enhance response.

    But as times and technology have progressed, so has the experience of enjoying turbocharged engines without the dreaded "turbo lag". Manufacturers have devised a number of ways to counter it and let's see some of them in brief :

    1. Compound charging/twincharging - using both a belt driven supercharger in conjunction with a turbocharger.

    2. Multiple variable sized turbos- using a smaller turbo in conjunction with a larger turbo. The smaller one gets the engine going at low rpms and the larger one takes over later. For e.g. The BMW N57S engine using 3 turbochargers.

    3. Torque fill - The most recent concept and till now restricted to exotics. The cheapest car to use this technology is the BMW i8 I guess. The electronic motor provides low rpm torque which aids acceleration and counters the feel of the turbo lag until the turbo engine is making full boost and consequently full power. It makes the power delivery seem completely linear. Other notable uses : P1, LaFerrari etc

    4. Better technology in turbos and exhaust manifolds - The BMW N63tu engine of the M5 placed the two turbos inside the V of the engine to reduce the path travelled by the gases significantly leading to reduced turbo lag. With turbo technology on the rise, you have turbos which spool up real fast leading to reduction in turbo lag.

    Basically - yes. It was true for a lot of time and still is true for economy cars or anything apart from exotic cars. It is the same "no free lunch" thing. Traditionally, turbo cars ran out of breath pretty soon because unless you put in a big turbo which is happy at high rpm, the engine will not be comfortable there. But if you do so, then you invite tonnes of turbo lag. Manufacturers have walked a middle path unless the vehicle was exotic etc. But as I said earlier, technology has progressed vastly and cars like BMW M3 are using evolved turbo tech leading to minimal turbo lag while still being able to spin the engine upto 7600rpm - something unheard of in a factory stock turbo car. And not just spin the engine but make power till that rpm.

    But in exotics using "torque fill" manufacturers have slapped on huge turbos on engines leading to huge power and no turbo lag because the electronic motor counters the "feel" of the turbo lag. :)

    Cheers.
  10. prabhjot

    prabhjot Esperto

    Messages:
    2,451
    delhi ncr
    many thanks man! very useful to know, this stuff.

    Interestingly, though OT: ChryslerFiat's developing new four- and six-cylinder turbo-ed, direct injection petrol engines, with the brilliant MultiAir VVT system, for the new Alfa-s (at the famous 'Skunk Works' experimental facility for new Alfa-s) and to meet the tough as hell CAFE efficiency norms in the US and similarly tough norms in recessionary Europe.

    We in India will surely NOT get any of that good stuff, not even on the Jeeps which will all be turbodiesels one suspects! Maybe if and when Fiat introduces Alfa Romeo here.

    Well, the 1.6 mjd and T-jet are ample for Fiat in India, i guess, wish they'd just hurry up the entry of the former! What needs turbo-charging are Fiat's Linea sales! ;-)

Share This Page