Pat Symonds has suggested that Formula 1's three top teams will get an advantage by spearheading the track development of the new, bigger Pirelli tyres for 2017.
A 24-day separate track programme on specially-modified older cars will begin in August, shared equally between top teams Mercedes, Ferrari and Red Bull.
F1's fourth-quickest team is Williams, whose technical boss Symonds thinks that the Pirelli programme will advantage the top three.
"Lotus went through its golden era when Pirelli was using their car," he is quoted as saying by Brazil's UOL. "It's a huge advantage and I think something we need to consider.
"They are blind tests but what guides the direction of development are the comments. When Lotus was testing they would say what they liked and what they didn't like, and based on those comments, Pirelli developed."
"So those who will do the [2017] testing have an advantage, and we can't participate. It's very expensive. Pirelli is paying for it in part, but not covering all of the expenses, so we can't be a part of it."
Williams currently trail third-placed Red Bull with 92 points to 198.
