The UK-based team managed a sensational leap in 2014 from ninth in the championship in 2013 to third in 2014 behind only Mercedes and Red Bull.
Some of that leap was undoubtedly due to using the field-leading Mercedes engine but Williams also comfortably beat Mercedes two other two customers, McLaren and Force India.
NEW RULES
However, for 2015, Symonds has admitted the 2014 concept had to be substantially changed to accommodate the new rules.
The International Automobile Federation reacted to the unseemly ant-eater-style noses of 2014 by tidying up the regulations and on the cover of British magazine F1 Racing it is now clear the front of the 2015 Williams is substantially different.
"The change in regulations offered us a slight headache," Symonds admitted on Wednesday (Jan 23). "The new front bulkhead and nose geometry had much more of an impact than we initially anticipated and the effect on the aero was profound."
The new FW37 has a smaller, flatter and lower nose than its predecessor, though it is still a stubbly protrusion.
Symonds said: "The team has worked hard on pulling back the deficit these regulations have made for us."
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