Williams FW33 – Lowline gearbox

Williams said their new car would be aggressive, but at first look the FW33 seemed quite conventional.  Until the area above the gearbox is looked at.  In order to gain the maximum flow towards the lower beam wing, Williams have removed a large part of the gearbox case (as described in the below illustration shaded yellow) ,lowered the differential and reworked the rear suspension.

In fact Williams Design team have completely rethought the rear suspension and gear case. By going to a Pullrod set up, the rockers, torsion bars and dampers that normally occupy the space above the gearbox are sited low down at the side of the gearbox (see https://scarbsf1.wordpress.com/2010/10/10/red-bull-pull-rod-suspension-what-is-looks-like-how-it-benefits-aerodynamics/).  Without this hardware mounted so high up,  the area above the gearbox is just a void. So although it serves a structural purpose the stiffen the suspension mounting points.  If they can be sufficiently stiff, then this area can be removed. Thus with the Williams the air flows over the upper body and around the engine cover, the bodywork then curves in behind the engine and airbox in a sharp “V”.   There is then no structure to hinder the airflow, until the air passes around the rear wing support, which now doubles up as the top rear wishbone mounting.

To remove other elements in the air steam, Williams have removed the toe link from behind the driveshaft and replaced it with a “Z” link upper wishbone. The slim carbon fibre moulding acting as both suspension members.
Further lowering the rear end the differential is lowered as far as possible. The differential is driven from the cross shaft between the diff and the main gear cluster. The differential can effectively be at any angle pivoted around the centreline of the cross shaft. What Williams have done is to lower it as far as possible while still allowing the CV joints some consideration and the starter shaft to be accessed.  This does effectively make the gearbox slightly longer.

One fear from the outsiders point of view would be the structural efficiency of such a waisted design, especially the vertical spar, that supports the wishbones leg above the differential. Williams would either have to compromise weight or stiffness to make the design efficient. So despite the loss of a large proportion of the gear case, the gain may be offset by the penalty of added weight to make the remaining structure stiff enough.

This gearbox has been a long lead time project, Sam Michael told me the new case was planned as early as March last year and the hard worked CV joints and driveshafts are designed and made by Pankl. They have no worries about the set ups reliability, although the joints are installed with such an extreme angularity, that they would either rob power or reliability with a normal design joint.

So complex is this set up, it would be near impossible to copy during the season.  As this would require new rear crash structures which are now homologated.  Not to mention the lead time and cost involved in developing a new gearcase and driveshaft solution.

26 thoughts on “Williams FW33 – Lowline gearbox

  1. Pingback: Tweets that mention Williams FW33 – Lowline gearbox « Scarbsf1's Blog -- Topsy.com

  2. This just looks amazing, and when its so different I guess its either going to be a great success or a disaster. I hope its takes them to the front as they deserve it.

  3. Amazing job for williams, and for you!!!

    One doubt, HRT will be using williams gearbox this season, that would mean that they will be using the same configuration?

    • I agree this is a really exiting development. It might be a trend towards real innovation again, not just playing with airflows by putting the nose up or the sidepods down.
      The exhaust thing is clever, but this is really an agressive design. Let us just hope Williams can finally get it to give them an on track benefit for at least some podiums this year.

  4. Pingback: Formel Eins: Jerez Test Tag 4 & Fazit /  RacingBlog

  5. I wonder if Williams looked at something like the Thompson coupling if the shafts are running at angles like that all the time. Thanks for your awesome site Craig, my favorite read on the way to work.

  6. Great article.
    As mentioned, moving to pullrods, allowed Williams to get rid of the top part of the case ahead of the final drive. Mechanically, I think the biggest thing is how they have lowered the differential itself, to take advantage of the low diffuser heights. I wouldn’t think that there is too much risk with this, if they use a proven gearbox mechanism, just in a smaller case…..

    And incidentally, F1 cars don’t use CV joints anymore. They typically use tripod joints, (stronger, lighter, more efficient) There is a pic of these on the Pankl website. As far as I know, Pankl supply most of the grid. I know that Lola used tripod joints as far back as 1993, in their Formula 3000 car….



    • I could understand tripod on the inboard side, but it was my understanding that most cars on the grid used a “heavily modified” version of a Rzeppa joint. I’m no expert obviously.
      Either way it’d be interesting to see f1’s take on a Thompson coupling. Fundamentally better than both (sweeping generalisation made without seeing what’s actually being used now) 🙂

  7. Williams has no doubt raised the ante in F-1 this year. A very clean design that promotes good airflow to the back of the car along with an improved lower center of gravity. I expect Williams to be a front runner this year and watch their competitors follow suit. My hat is off to the Engineering staff at Williams for a job well done. I look forward to its success!

  8. Pingback: Williams e o segredo do FW33

  9. Pingback: F1 Constructor: Williams | Georgegumm's Blog

  10. Pingback: Williams FW33 Interim Livery pictures ( 1st of February)

  11. Pingback: Williams FW33 Interim Livery pictures ( 1st of February) | Fairy Famous

  12. Pingback: Launch Analysis: McLaren Mercedes MP4-27 | Scarbsf1's Blog

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s