Following the introduction of the RTA48T and RTA58T models in
1995, the same design concepts were applied to the RTA84T ‘Tanker’
engine—originally introduced in May 1991—resulting in a Version B
in 1996. Easier manufacturing and enhanced service behaviour were
realised, with no change in power output. In July 1998 a lower specific
fuel consumption (down by 2 g/kWh) was gained by applying ‘low
port’ cylinder liners (scavenging air inlet ports with a reduced height)
in combination with higher efficiency turbochargers. There is no penalty
in either higher component temperatures or too low exhaust gas
temperatures, and the low ports give a longer effective expansion
stroke in the cycle (Figure 12.23)