SCRATCHING HEADS: Daniel Ricciardo drives his Red Bull during testing in Spain. Image: AP / Manu Fernandez.
BERLIN, Germany - Renault has made progress but not enough to topple dominant Mercedes.
That is the admission of Red Bull chiefs Christian Horner and advisor Helmut Marko, although they are confident works supplier Renault is on track with a better engine for 2015.
It has now been tested at Jerez and Barcelona and lead driver Daniel Ricciardo revealed last week the 2016 power unit "definitely has some more ponies".
'NOT EVENLY DISTRIBUTED'
Team boss Horner confirmed to Germany's Auto Motor und Sport: "It does have more power but it is not evenly distributed. There is still a problem with driveability."
Marko said some of that problem can be solved through software changes.
"Then we will have caught up a large part of Mercedes lead," he predicted.