It seems that also ferrari has made a secret test for Pirelli at the beginning of May in Barcelona:
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(picture from the autosport forum)
The car used was a 2011 - not 2013 car; it was also operated not by the race team, but by the Group that attends to promotional events (this not making any big difference).
Details in this article by adam cooper, found via @scarbsf1 in twitter:
http://adamcooperf1.com/2013/05/30/ferr ... elli-test/
To me it is surprising how this thing has passed under the radar, compared to all the mess around Mercedes test.
In my opinion, but people knowing more about vehicle dynamics know better, using the 2011 car gives the team a lot of information anyway on the tyres useful for 2013, if you can correlate the energy put in the tyres by a known car to the tyres behaviour.
Does this pre-event test correlate to the excellent Spanish gp performance of ferrari?