F1 testing: Honda has gained 166kW!

Honda has aced its winter off-season following the Japanese automaker's woeful return to F1 in 2015.

That is the claim of Manuel Franco, the correspondent for the Spanish sports daily AS.

He says the Honda power unit for 2016 is an incredible 166kW better than the one with which Fernando Alonso and Jenson Button finished in 2015.

Closing the gap

He said the feat has been achieved by closing the 52kW gap to the leading internal combustion engines of 2015, plus solving the 121kW deficit caused by Honda's troublesome energy recovery systems.

"Sakura, the Honda factory in Japan, has worked 24 hour shifts without Christmas holidays," wrote Franco, amid other reports suggesting the McLaren chassis has passed the FIA crash tests.

The positive speculation about McLaren-Honda's preparations also appear to be leaking into the world of bookmaking, with Brazil's UOL saying Alonso is listed as the fourth favourite for the 2016 world championship.

Ahead of him are the two Mercedes drivers and Sebastian Vettel, with Alonso tied with Ferrari's Kimi Raikkonen and ahead of the Williams and Red Bull drivers.

Spain's El Mundo Deportivo, meanwhile, says the first MP4-31 chassis is now being assembled at Woking, after the chassis passed the FIA's frontal crash test at the weekend.

The report said the car has a short, Red Bull-like front nose, and similar 'size zero' packaging as in 2015.

2015 Manor driver Roberto Merhi, however, is not sure his countryman Alonso can be targeting this year's world championship.

Merhi added: "It is my opinion and I could be wrong. They say they evolved a lot in the last race but it was still far from the best. Let's wait a couple of races to see."