04/03/2015
NEWS STORY
Lotus technical director Nick Chester buoyed by positive pre-season testing following engine switch.
The switch from Renault power units to Mercedes is already paying off, according to Chester. Though the Enstone outfit was only the seventh 'busiest' team over the course of the twelve days, its 2,628 miles compares extremely favourably to the 800 miles completed in 2014 when struggling with the new Renault unit.
"This year is looking a lot better," admits Chester, "the power unit is a big step forward. The chassis is also a step forward, the drivers can get a lot more from it and it's easier to drive on the limit as well as being more predictable.
"We spent some of the test exploring the E23's suspension geometry and it has a lot of effect on the balance of the car in the middle of the slow speed corners. We're also making the car less sensitive for the drivers so it's easier to extract performance.
"The power unit has strong performance and response and it's extremely reliable, we've only used one unit throughout testing. Its installation is nice which gives us some benefits, such as the way we've organised our cooling system.
"The response of the power unit in addition to peak power does play a significant role and we have found that tuning our control systems has been made easier with a very responsive power unit," says Chester. "I don't think our approach changes as we're always aiming to make the car better. The area where we didn't take too many risks was the engine installation. We wanted to be reasonably comfortable with cooling and we've been quite conservative ahead of Melbourne. The rest of the car is our usual approach, pushing the boundaries as we try to keep finding improvements.
"It's been a challenge to fit the engine as the rear surface of the chassis is quite different and we had to do a lot of work to have a neat installation," he admits. "We've gone back to air to air charge air cooling because the packaging switch to Mercedes power on a short timeline meant we had to find a simple solution."
Asked about upgrades and the intended development programme this year, he replies: "There's been some updates throughout testing and some more minor ones are on the way for Melbourne, with the bigger upgrades planned for rounds two and three.
"We (will) have a normal programme through the race weekend, it won't be particularly conservative and will be about maximising the car. We take a view based on risk for fitting development parts, sometimes there is minimal risk for extra performance so parts can be introduced immediately. Sometimes there can be a downside and you need to accumulate mileage for a few practice sessions before fitting for qualifying and the race.
"It's massively different in 2015 compared to 2014, straight out of the box we're running over 100 laps a day without problems. Given the number of changes, I'm pleased with the running and limited problems we've had."