Original URL: http://www.theregister.co.uk/2008/01/25/tesla_transmission/

Tesla shifts gear out of park and into interim

One gear fits all?

By John Oates

Posted in Science, 25th January 2008 11:43 GMT

Tesla has confirmed that the first models of its electric sports car will ship with an interim transmission which reduces expected acceleration.

Production will start in a limited way in March. Early buyers will get a free upgrade to the transmission and engine when they are available later in the year.

The first production car will be delivered to Tesla chairman Elon Musk next week, but series production will start 17 March. The transmission issue means that production will be limited until the new unit is ready some time later this year.

The interim transmission means the car will take 5.7 seconds to get to 60 miles per hour - which is quick but hardly exceptional for a sports car. The replacement transmission will achieve the original spec of getting to 60 mph in four seconds.

But Tesla is doing its best to put a positive spin on the transmission problems, claiming: "Instead of a complex 2-speed transmission design, Tesla will achieve the original performance goals with a simpler one-speed unit mated to a higher rated Power Electronics Module (PEM)."

The changes mean the existing motor will need extra cooling to deal with the extra power.

The company said the replacement transmission plan: "reduces program risk, provides better efficiency, lower weight, equal or better range, better thermal performance and quicker quarter mile acceleration due to the elimination of the need to shift gears."

The car has now got regulatory approval for car safety and emissions. ®