HONDA S 2000 - Drivetrain

- 240 PS at 8,300 rpm, redline at 9,000 rpm
- 120 PS/litre new record for mass produced, normally aspirated engine
- Engine remarkably compact and located behind front axle
- Design concentrates on breathing efficiency, component strengthening, inertial weight and friction reduction
- Uses Formula 1-inspired technology including forged aluminium pistons, lightweight valve springs, 11:1 compression ratio
- Latest generation of DOHC VTEC features roller-type rocker arms produced by world-first metal injection moulding process
- Advanced emissions equipment achieves compliance with Californian LEV, European EU2000 and German D3 regulations
- Lightweight six-speed manual transmission allows rapid shifting

A normally-aspirated, four cylinder engine producing 240 PS at 8,300 rpm from a 2.0 litre displacement is little short of staggering and strong justification for describing this latest VTEC engine from Honda as an engineering masterpiece. What makes the achievement all the more exceptional is that the HONDA S 2000 also meets the strict Californian Low Emission Vehicle (LEV), EU2000 and German D3 emissions requirements.


New benchmark figure

120 PS/litre is a new record for a mass-produced, normally aspirated engine, dramatically redefining the global standard in specific output. The benchmark had already been set by Honda: the 190 PS 1.8 litre engine of the Integra Type-R has a specific output of 105.7 PS/litre, while the (Japan only) 185 PS 1.6 litre Civic Type-R achieves 115.6 PS/litre.

There is a tendency for terms such as 'race-bred technology' to be used where their application has little justification, but in the case of Honda's brand-new engine, the term genuinely describes the engineering influences behind its development. Many of the design team were part of Honda's all-conquering Formula 1 engines team as well as being involved with the current US CART programme.

Attaining the necessary levels of power required for a high performance sportscar from a 2.0-litre four cylinder engine, at the same time providing suitable refinement and emissions performance, calls for some particularly advanced engineering solutions. Honda's engineers chose a four cylinder configuration primarily for its packaging benefits: the compact dimensions mean the engine can be positioned well back in the engine bay to the benefit of handling. It is also lighter than a V6 of equivalent capacity.

Turbocharging would have been the simplest way to boost power, but Honda chose instead to enable the engine to run at higher revs; more power can be extracted at high engine speeds since more revs mean more power strokes. However, such an approach means that the problem of higher frictional losses and increased stress on components has to be addressed.

Honda has always had a reputation for producing high-revving engines, but according to chief engineer Shigeru Uehara, when moving past an 8000 rpm maxima, "new noise and vibration patterns were discovered. This was an 'untried zone' for us." His response to this technical challenge was not only to concentrate on advanced detail engineering, including lightweight, high precision valve gear, but also to painstakingly reduce inertial weight and operating friction, in both engine and key ancillary components, as well as ensuring good breathing efficiency. By combining advanced design and materials, plus key racing-inspired technologies, the Honda team achieved exceptional engine efficiency.

previous page | go to page 5