Pirelli motorsport boss Paul Hembery says that teams won't show their true colours when pre-season testing gets underway at Barcelona at the end of February.
Formula 1's huge technical regulation overhaul have forced teams to start from a clean design sheet this year, and while everyone is hoping for upheaval of the running order, Hembery doubts anything conclusive will come away from the test.
"We really won't know in Barcelona testing where the teams are as that's a period where they won't want to show their hand," said Hembery when he visited Autosport International in Birmingham.
"There will be a lot of people trying to hide their true performance level or maybe wondering what they need to do because they can't even get close to some of the teams who are maybe sandbagging."
Indeed, he even believes that a true reflection of the grid's relative performance won't appear until the second or third rounds in China and Bahrain.
Pirelli has announced that its 2017 compounds have been engineered to obtain a low level of degradation. But Hembery is also expecting 25% more grip and obviously fewer tyre changes
"The problem we have got is that we have been testing with cars that are five seconds slower than what we're actually going to see in Barcelona.
"From a compounding aspect, it is a bit of a challenge for us because it's a very small window we're working with.
"If the numbers aren't what we have been told they are going to be, then we might have been a bit too conservative."