Renault's takeover of Lotus has led to the team requiring a new design for the majority of its parts in 2016.
Lotus switched from a Renault power unit to Mercedes last season, with an improved chassis leading to a stronger year than 2014 as the team scored 78 point including one podium. However, with Renault returning as a constructor and purchasing Lotus over the winter, the team is reverting back to the French power unit.
Technical director Nick Chester says last year's car still forms the basis of the team's 2016 design but more changes need to be made to accommodate the new engine.
"It’s the third year under the current regulations so it’s natural for this year’s car to evolve from the E23 on a design front," Chester said. "Some parts will share the same design although with a change of power unit, the majority of the parts are a new design.
"I’m pleased to say we are working on [the new car] fully on all fronts and looking forward to seeing it hit the track."
And Chester says last year's E23 will go on to be a show car having last been run at the Pirelli tyre test in Abu Dhabi.
"It came back and was stripped down; parts were inspected and serviced. At the moment, both E23s are totally stripped down and sitting there as bare chassis. They only exist in kit form right now really.
"Each part is logged and tenderly cleaned then ‘filed away’. Now it is all about the 2016 car and there’s plenty of work to be done before testing begins."
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