On the one end of the gearbox lives the engine with clutch, and on other end differential - an essential part of the drive train where drivability is concerned. As it travels around a corner, the car will map out a curved path the width of the car itself.

The inside arc of the path will be of tighter radius than the outside one, and so the wheel on the outside will have to travel further and so rotate at a different (higher) speed to the wheel on the inside. If the two wheels were directly connected, the loaded wheel (on the outer, longer arc) would force the inner wheel to rotate at the same speed, and the tire would spin and scrub along the ground. To solve this, in sport cars and F1, the 'limited-slip differential' is used, compared to open differentials used in most family cars.

Internals of an Limited slip differential

Internals of an Limited slip differential in sport cars
Limited slip diff
Internals of an Limited slip differential in sport cars



Open slip differential in road car
Open slip differential in road car


Open slip diff
Open slip differential in road car
Formula 1 differential with ring gear visible
Formula 1 differential with ring gear visible


The open differential theoretically delivers equal torque to both drive wheels at all times, whereas a limited slip device uses friction to change the torque relationship between the driven wheels.

This allows the sport car wheels to roll at separate speeds to each other when the car is entering the corner, then as the driver comes back on the power, the differential will slowly lock up to avoid the inside, unloaded wheel spinning. Of course, like most things on a Formula One car, this is all electronically controlled, and can be programmed into the car - in fact, until it was banned, there was a button on the steering wheel which drivers could press to manually lock or release the diff as they pleased, enabling them to get better traction out of the corners.
Electro-hydraulic devices are used in F1 to constantly change the torque acting on both of the drive wheels at different stages in a corner. This torque relationship can be varied to 'steer' the car through corners, or prevent the inside rear wheel from spinning under harsh acceleration out of a bend. The FIA allows the use of these devices provided that their Characteristics are fixed once the car is out on the track.
A Moog electrohydraulyc valve (from RaceCar-Engineering, Charles Armstrong Wilson, 2008) will constantly adjust the friction between the two shafts around the track to maximize the performance of the car dependent on what characteristics have been entered into the on-board computer.

Moog valve

The Moog valve opens and closes depending on what the software is telling it to do, but the valve must work to the same set of conditions that are pre-programmed whilst the car is in the pits. This means that the driver cannot actually alter the characteristics of the differential due to a change in tracks conditions for instance, which was allowed in the days of the many driver aids around 1993.

A Moog valve is based on technology developed during World War Two due the need to convert an analog electrical signal into a proportional hydraulic oil pressure differential which in turn drives a spool valve. this valve controls the flow, pressure and flow velocity of hydraulic actuator or cylinder. Moog valves are popular in Formula 1 because they control equipment with precision and with very high response and therefore facilitate the operation of all servo-hydraulic control systems currently used.










The wineglas and champagne bottle cork provide a remarkable
prospective for this ZF Sachs Formula 1 clutch. Though tiny,
only 111 mm in diameter, it can transmit more than 900 horse power.


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Books to read

Noko Lauda RIP
Niki Lauda, one of the biggest names in motorsport, both on and off the track, has passed away peacefully at May 20, 2019 in Vienna, Austria, aged 70. "With deep sadness, we announce that our beloved Niki has peacefully passed away with his family on Monday," his family said in a statement issued to Austrian media.
He was a three-time Formula 1 world champion and non-executive chairman of the world champion Mercedes team. He'd been unwell for a while, but I'll always remember him like this: flying high, flat-out.
Thank's Niki for the inspiration you have been to so many, the amazing speed & fighting spirit you had. We will miss you, but never forget you.
My condolences to Niki's wife Marlene and children Mathias, Christoph, Lukas Max and Mia. Also, my
condolences to Mercedes team.
We'll miss you, RIP Niki.
Ruhe in Frieden Niki.
RIP Niki Lauda

Some useful links:

- f1technical.net, a great site with a lot of technical information’s and explanations. Site is updated daily with news from F1 word.

 - autosport.com, This site is a legend. A bible for racing lovers. News from all around the word. Unfortunately, to get access to all news, interviews and to open the site completely you should be subscribed to Autosport magazine. Anyway, great read.

James Allen on F1
- JA.F1 site (or blog) ovned by ITV Sport’s lead commentator on Formula 1 James Allen

Joe Saward blog
- joesaward is the Joe Saward official blog about Formula 1 world. Joe is an journalist, who write primarily about politics in and around motorsport, specifically on the FIA Formula 1 World Championship

Vital F1
 - vitalf1.com/ is another great site for Motor Sports fan’s like me. Site is relatively new, but great fun, with great discussion forum, Formula 1 news and forum.

 GP update
- f1.gpupdate.net, Site with fresh news from Formula 1

Planet F1
 - planetf1, another site with many different articles, news and statistics. Biased toward British teams, but anyway good read.

Gurney flap
 - gurneyflap.com, Great history site. You can learn a lot from this site. Pictures, cars and many many more. Great.

4ormula1 is a database of Formula 1 history and statistics of drivers, teams, grand prix, and all results since 1950.

Missed Apex Podcast
Enjoy range of Podcasts and Articles on Motorsport. Every week a Formula one chat on Missed Apex F1 Podcast with F1 journalist Joe Saward and tech Analyst Matthew Somerfield as guests. Also the exciting all electric racing series formula E on eRadio Show and Bike Show Lean Angle Podcast.

Racecar engineering
-Racecar Engineering, an online magazine with a lot to learn from, a lot of technical information’s and explanations

 - fia.com, La Fédération Internationale de l'Automobile, representing the interests of motoring organisations and motor car users. Head organisation and ruler in auto sport.

 - wikipedia.org, I don’t believe that I have to tell you anything about this site. It’s not about Formula 1 technology, but you can learn a lot about that too.

Sutton Images

grandprix photo

 - carbibles.com, a great site for normal car users. Here you can find explanations of almost everything about your car and how it works. Technical reviews and explanations of some in-car gadgets.

Dare To Be Different
- Daretobedifferent.org Susie Wolff and UK governing body of UK motorsport have joined forces to launch Dare To Be Different, a high-profile new initiative which is about increasing female participation, not just on the track but in all aspects of the sport.

Giorgio Piola web site