+ Reply to Thread
Results 1 to 7 of 7
Like Tree1Likes
  • 1 Post By No Lotus

Thread: Ferrari pullrod (vs. pushrod) suspension.

  1. #1
    Senior Member
    Join Date
    Sep 2011
    Location
    Rolling Hills Estates
    Posts
    3,003
    Liked
    887 times

    Default Ferrari pullrod (vs. pushrod) suspension.

    Per the link below and Speed Channels commentary, Ferrari laid an egg with its suspension redesign.

    F1: Ferrari suspension not seen in F1 since 2001 Gene | FerrariCircuit

    Can anyone explain the real difference between these suspension types?

  2. #2
    Senior Member
    Join Date
    Sep 2011
    Location
    Rolling Hills Estates
    Posts
    3,003
    Liked
    887 times

    Default

    Hmm . . . .

    I did stumble across find a very thorough explanation below. Could be good for some of you guys; but, unfortunately, it is a pay grade or two over my head.

    Red Bull Pull Rod suspension: What is looks like – How it benefits aerodynamics | Scarbsf1's Blog

  3. #3
    Senior Member No Lotus's Avatar
    Join Date
    Oct 2007
    Location
    SF/Reno
    Posts
    159
    Liked
    3 times

    Default

    I've heard or read that the supposed advantage is in terms of aero. Because it bears most load in tension, the pullrod may be thinner than a pushrod that works in compression. Because of the geometry of the double wishbone suspension in the front, the pullrod is also shorter than an equivalent pushrod. The negative supposedly has to do with shock damping. I think something to do with an inferiority compared with a pushrod arrangement in dealing with rebound.
    Loose Caboose likes this.
    2005 Noble M400, upgraded to 500+ hp.
    2005 Elise S2 SCCA T2 legal

  4. #4
    Senior Member
    Join Date
    Sep 2011
    Location
    Rolling Hills Estates
    Posts
    3,003
    Liked
    887 times

    Default

    Thanks! Your response seems largely in agreement with another part of the same blog. Seems like aerodynamic advantage did drive this change, but that the primary advantage is its more horizontal position.

    (excerpt below)
    ----------------------------------------

    A mention of front suspension in the cars launch analysis will be unique to Ferrari this year, as they have revisited an old direction with its layout. Every other car for well over ten years has had pushrod front suspension, but Ferrari has revived the pullrod set up for the front of the car.

    This effectively turns the pushrod set up upside down, now the rod passes down from the upper wishbone and connects with the rocker, which is now mounted at the bottom of the chassis. According to Fry, this set up is a little lighter and has a slightly lower Centre of Gravity. These gains alone will not pay for the systems inclusion on the car, so the team claim to have found an aero benefit. The pullrod can be thinner, but the real gain is the pullrod is mounted near horizontal across the front suspension. This places it in line with the upwash from the front wing. Just as with the wishbones, its profile can be subtly altered within the rules to help control the wake from the wing and improve the airflow over the rear of the car. Despite appearances the pullrod is as effective in moving the rocker for a given wheel travel as a pushrod. The important factor is the angle between the rod and the wishbone is connected to, rather than the rods angle to the chassis. Ill explain a lot more pull rod suspension in a subsequent article
    Last edited by Loose Caboose; 03-18-2012 at 07:25 PM.

  5. #5
    Administrator ucfbrett's Avatar
    Join Date
    Jan 2009
    Location
    Ventura, Calif.
    Posts
    5,646
    Liked
    2361 times

    Default

    I believe this means the suspension acts against the spring in an opposite direction. In other words, compression and rebound are reversed. When the suspension compresses, it's actually pulling against the spring rather than compressing it.

    Buell Motorcycles used a similar setup under the engine of its bikes. When the rear wheel traveled upward, the spring extended rather than compressed.
    Of course, I could be wrong.

  6. #6
    Senior Member
    Join Date
    Sep 2011
    Location
    Rolling Hills Estates
    Posts
    3,003
    Liked
    887 times

    Default

    Our modest administrator nailed it. See below:

    Formula 1

  7. #7
    Faster than Oli jimt's Avatar
    Join Date
    Sep 2009
    Location
    Orange County, CA
    Posts
    674
    Liked
    454 times

    Default

    According to that link, yes it is reversed. But an inverted damper/spring isnt inherent to the pull rod design. Its a function of the rocker. The rocker can be arranged to compress the spring when the wheel is in bump.
    ~ Jim Tway
    Tway Motorsports
    (714) 528-2150
    #57 Pacific Automotive Recycling Center Corvette

    Brought to you by:
    Pacific Automotive Recycling Center
    PA Construction
    American Heritage Performance

+ Reply to 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