| Turbochargers, not direct injection,
could be the technology OEMs turn to first to boost gasoline engine efficiency.
Their lower cost could mean faster adoption rates in downsized engines
for entry-level vehicles.
Downsizing is the accepted route to achieve lower fuel consumption and
CO2. Turbocharging and GDI offer the most potential but at a cost. Forced
induction of traditional port injected (MPFI) engines is an attractive
compromise.
Turbocharging of either GDI or MPFI can improve fuel economy. Turbo GDI
engines can use around 15-20 per cent less fuel than naturally aspirated
variants; a turbo MPFI 5-15 per cent less.
Honeywell Turbo Technologies marketing director David Paja said: “GDI
penetration in Europe will increase from around five per cent to more
than 30 per cent of all gasoline engines by 2012. Boosted MPFI engines
with variable valve timing may still have a significant share of demand
– it represents a cost-effective option for the entry segments.
“Given the lower system costs of MPFI over GDI, Honeywell expects
turbo penetration to grow faster than GDI penetration.”
VW is taking turbo GDI into the mass market with the 1.4-litre TSI engines
in the Golf and, soon, the Polo. But Renault has opted instead for turbo
MPFI for the 1.2-litre TCE 100 engine used in the Clio and Twingo. Fiat
took the same approach with the 1.4-litre T-JET engines for the Bravo.
A top speed of 325km/h (202mph) requires massive airfow for induction and cooling systems, provided by vents and scoops in the C-pillars and the carbon fibre roof. Alterations to underfloor aerodynamics and a lower ride height ensure that the car stays on the road. |
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