The Atkinson cycle sacrifices low - end torque for greater
efficiency at higher rpms, the low - end torque being supplied by the electric motors in a hybrid.
In DOHC engines a shorter stroke and a larger piston can allow for a higher RPM and more
efficiency at higher RPM's due to less reciprocating weight related to the connecting rods, pistons and crankshaft.
Not exact matches
With an automatic transmission this is very difficult because if you try to run the engine
at wide open throttle the automatic transmission will extend your shift point up to the
high RPM range and you will get very bad BSFC and in turn
efficiency.
The improvements in low -
RPM performance, which is where most street - driven automobiles operate a majority of the time, occur in trade for a power and
efficiency loss
at higher RPM ranges.
This increases
efficiency at low
RPMs and a lot of power is accessible
at high RPMs; definitely more than a VVTi.
VTEC (Variable Valve Timing & Lift Electronic Control) is a system developed by Honda which was said to improve the volumetric
efficiency of a four - stroke internal combustion engine, resulting in
higher performance
at high RPM, and lower fuel consumption
at low
RPM.
By operating the engine
at higher load and
at lower
rpm, optimal
efficiency can be obtained.
The inertia effect greatly enhances cylinder filling
efficiency and the torque produced by the engine
at higher rpm.
The effective - compression ratio is less than 9:1
at low -
rpm speeds for good drivability and much
higher at high engine speeds for increased
efficiency and power.
Eco shifts gears early for better fuel
efficiency, Sport shifts gears
at high RPMs to extract optimum power while Manual lets you choose the gears though it shifts automatically after redline.
This kept torque levels
at near - peak levels throughout the rev range and allowed a
higher maximum horsepower without killing fuel
efficiency or hindering drivability
at lower
rpm levels.
Every 2013 GMC Sierra HD features a standard 6.0 - liter Vortec V8 with cam - in - block variable valve timing (VVT), which provides more power
at high rpm and better fuel
efficiency.
Advanced engineering techniques such as rapid - multispark ignition and
high - pressure direct - injection help the GLA250 achieve 258 pound - feet of torque
at 1,250
rpm while also enhancing fuel
efficiency.
This Ti - VCT engine, delivering
at least 280 horsepower and E85 compatibility, is mated to a unique six - speed automatic transmission that combines lowered initial gears for improved off - the - line acceleration and
higher gearing for improved
efficiency at lower engine
rpm when cruising.
Boasting
higher torque
at low
RPMs and greater output for smooth top - end power, MIVEC technology mixes together fuel
efficiency with sporty performance while minimizing harmful emission.
A low - friction three - cylinder architecture that delivers naturally
high torque
at low
rpm An integrated exhaust manifold that improves fuel -
efficiency by helping the engine reach optimal temperatures faster, and delivers torque more rapidly by minimizing the distance exhaust gasses travel between cylinders and turbocharger.