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Old 01-02-2012, 10:22 PM
MCSL MCSL is offline
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Location: Nor Cal
 
Join Date: Jan 2005
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Mein Auto: 330i
Xtrac has been selected as the sole gearbox supplier to Dallara for the 2012 Indycar. For the new car the English firm has developed a new transmission dubbed the 1011. Engineer Adrew Heard reveal more about the new cars gearbox.

We are adding more tuneability, if there is such a word. Expect there to be a few more options that will allow the engineers to tune the transmission more with more options in set up. We are also incorporating into the design many of the features that have been added onto the design of the current gearbox since it was first introduced. Key things that have happened since 2003 is that a differential was added for road course racing and then a paddle shift system was added. Reverse was the most recent thing to be added. All these features have been designed in since the initiation of the project, which allows for nicer packaging with less add-ons.

We have designed it for slightly higher torque capacity. We are trying to keep the weight down but maintain the safety record as well in terms of such as tethers and lights on it. We have had a good track record there and we do not want to be moving backwards.

It is still a six speed plus reverse and the differential will be adjustable.

The main Megaline GCU is a carry over from the current car but there will be firmware/software updates. It will be communicating with a new ECU. The new cars will have drive by wire throttle, as opposed to a pneumatic blipper so the GCU needs to communicate differently. The valve block is similar in operation but we only need two valves instead of three because there is no throttle blipper. We are integrating the actuator into the casings rather than being a bolt on part.

Paddle shifters undoubtedly bring cost savings to the teams in terms of gearbox inventory. Taking the driver away from direct control of the gearshift is good. However good the drivers are, errors still used to be made and you got damage to the transmission. We have seen over revs of the engine go to zero. I understand that avoiding one over rev rebuild pays for the paddle shift system.

http://www.racecar-engineering.com/a...-transmission/
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