Is the engine crackle and burble on the over-run when in sport mode bad over time? - Page 2
Page 2 of 2 FirstFirst 12
Results 21 to 24 of 24

Thread: Is the engine crackle and burble on the over-run when in sport mode bad over time?

  1. #21
    Join Date
    May 2017
    Location
    NC
    Posts
    344
    Likes (Given)
    96
    Likes (Received)
    93
    Downloads
    0
    Uploads
    0

    Re: Is the engine crackle and burble on the over-run when in sport mode bad over time

    Here's a good read of how Jag does it on the F Type


    2014 Jaguar F-Type is calibrated for sonic delight - SAE International

    Calibrating a "controlled misfire"

    "'Theater' is a great word," noted Kevan Richardson, Program Manager for Jaguar sports cars. “We want the car to be entertaining. That’s why it has pop-up [HVAC] vents, a lighting cascade on start-up and a pop-up rear spoiler. It is all part of the show."

    "All of those little noises are usually the kinds of sounds engineers spend months trying to dial out," he acknowledged. "Because this is an unashamed sports car, we’ve recognized the noise the exhaust makes is part of the experience and something customers want."

    Jaguar engineers achieved this by defying convention. "Usually you’d cut the fuel to the cylinders, when the driver lifts off the accelerator," explained Andrew Lowis, the Gasoline Calibration Manager for the car. "We are delaying the point when we do that and igniting later than we might in normal circumstances. It produces a controlled misfire."

    Obviously, the car must still meet emissions regulations despite the intentional introduction of pollutants to the exhaust stream. "It is a challenge, but it is one we can achieve by careful calibration," said Lowis. In fact, Jaguar has more stringent internal emissions limits than the government applies, he said, and the car meets those, too.

    Regardless of the difficulty, it was necessary work, Lowis insisted. "The powertrain sound quality of this car was absolutely fundamental to the character of the F-Type."

    The burble through the pipes is made more audible by the use of muffler bypass valves that open to send the glorious noise directly out the back when the driver selects the appropriate drive mode and stands hard on the gas or lifts off abruptly. The bypass is standard equipment on both the V6 S and V8 S, and is an option for the base V6 car.
    2017 718 Cayman S - GT Silver, PASM Sport, PTV, Chrono, PSE, PDLS, Sport Seats +, Manual Gearbox

  2. Remove Advertisements
     

  3. #22
    Join Date
    Jul 2013
    Location
    N/A
    Posts
    764
    Likes (Given)
    384
    Likes (Received)
    268
    Downloads
    14
    Uploads
    0

    Re: Is the engine crackle and burble on the over-run when in sport mode bad over time

    Quote Originally Posted by R Doug View Post
    If you have the chrono package, the burbles and pops cease in Sport Plus mode (even with PSE engaged). Of course, the traction control also allows for more play in this mode, too.
    Interesting. That is not the case with the 981.

  4. #23
    Join Date
    Sep 2015
    Location
    Atlanta GA
    Posts
    985
    Likes (Given)
    77
    Likes (Received)
    281
    Downloads
    4
    Uploads
    0

    Re: Is the engine crackle and burble on the over-run when in sport mode bad over time

    Quote Originally Posted by canux View Post
    Interesting. That is not the case with the 981.
    Yep, complete opposite. Sport + makes them the most aggressive

  5. #24
    Join Date
    Jan 2007
    Posts
    4,824
    Likes (Given)
    372
    Likes (Received)
    1812
    Downloads
    2
    Uploads
    0

    Re: Is the engine crackle and burble on the over-run when in sport mode bad over time

    Quote Originally Posted by R Doug View Post
    That's what I'm thinking. And, more importantly, to chows4us' point on Ferrari, stress on the exhaust valves.
    The problem is I can't find any info on how PSE works. If extra fuel is injected into the cylinders when the exhaust valves are open, then it would be reasonable to assume that over time there could be exhaust valve damage. But unlike the naturally occurring popping in a racing engine, contrived popping can be achieved in other ways. All you need do is to get a tiny amount of fuel on a hot exhaust pipe.
    Last edited by fast1; 01-16-2018 at 10:50 AM.

  6. Remove Advertisements
     

Page 2 of 2 FirstFirst 12

Similar Threads

  1. Love all the lines and curves on the Cayman
    By harajuka in forum 987 Cayman and Boxster Pictures & Video
    Replies: 2
    Last Post: 02-19-2013, 08:45 AM
  2. MSpeed Cayman and others on the Ring in the Rain
    By Speed Racer S in forum 987 Cayman and Boxster Chat
    Replies: 5
    Last Post: 08-25-2007, 11:18 AM
  3. Does the car lower when in Sport mode?
    By Rhamy in forum 987 Cayman and Boxster Chat
    Replies: 2
    Last Post: 07-28-2007, 10:35 AM
  4. Competition tyres and brakes (on the street)
    By dt in forum 987 Cayman and Boxster Competition
    Replies: 3
    Last Post: 06-30-2006, 01:46 PM

Tags for this Thread

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
  •