Satisfactory debut for Mercedes V8 15 Sep 2005
Formula One regulations for 2006 require the current 3 litre V10 engines to be replaced by 2.4 litre V8s. This week saw McLaren test theirs on track for the very first time at Silverstone.
Pedro de la Rosa was the man at the wheel of the interim MP4-20B, a modified version of the teams 2005 race car specially adjusted to fit the new Mercedes engine. He completed 78 laps over two days with a best time of 1m 22.974 - between five and six seconds slower than the fastest V10 car present.
"The last two days of testing have gone well and we are on schedule with the development programme, said de la Rosa. There is obviously a big difference in power between the Mercedes-Benz V10 and the V8, and therefore I had to adjust my driving style.
In between runs over the last couple of days, the engineers have been analysing the data and making changes to the car. It is positive that we were testing with the new engine without problems and long delays. During this test we have also been looking at the difference in vibration between the Mercedes-Benz V10 and V8 engines; however we didn't find anything we had not expected."
Those vibrations remain the biggest challenge facing the Mercedes engineers, who first ran the engine, dubbed the FO 108S, on a dyno three months ago. It completed around 2000 kilometres on the bench ahead of its track debut and is estimated to have around 200 horsepower less than its V10 equivalent.
The engine has had to be designed and built from scratch, since the new regulations place much tighter restrictions on the manufacturers than before. A 90-degree cylinder V-angle is mandatory, with a maximum of two inlet and exhaust valves per cylinder (until now the rules have stated only the number of cylinders and a limit of five valves). The engine must weigh at least 95 kilograms and its cylinder bore must not exceed 98 millimetres. The position of the engine's centre of gravity and the alloys to be used in manufacturing its components are also strictly defined.
Mercedes began work on their new engine in the autumn of 2004 when a team of engineers drew up the first concepts. The design process lasted from Christmas to spring, a period during which the engineers also built one-cylinder models to test pistons, connecting rods and valve drives. After the dyno tests, this weeks maiden track outing was the next big step, and Norbert Haug, Vice President Mercedes-Benz Motorsport, was pleased with the results.
"We had an uneventful track debut with our new V8 engine, he said. With Pedro de la Rosa at the wheel we gained first basic experiences with the new engine on a race circuit and we completed our programme as planned. The data we collected during over 400 test kilometres will be analysed at Mercedes-Benz in Brixworth and will help us to develop the engine further as planned. The premiere was OK and everything goes exactly according to the plan we have set for ourselves."
The V8 engine will also significantly influence the design of McLarens 2006 car, the MP4-21. The V8 is smaller than the V10 and the new engine also needs less air than before. Therefore, there will accordingly be significant modifications to the aerodynamics for next year's machine, which will also use new, specially developed fuel and lubricants.