On the new Testastretta 11° engine, this angle has been reduced from
41°, used in the Testastretta Evoluzione engine which powers the 1198,
to just 11°. As a result, the fresh inlet charge flow is less
compromised by the exiting exhaust gases, resulting in a much smoother
combustion in addition to improved fuel economy and lower exhaust
emissions. Unburnt hydrocarbon emissions (pre-catalyser) are reduced by
up to 65% and specific fuel consumption (and consequent CO2 emissions)
by up to 15% (Euro3).