Thanks Jerry - What is variable valve timing and what is its
advantage?
Basically, they manipulate the timing of the intake and/or exhaust
valves, depending on conditions. There is no single timing that is
best for all conditions, so engines with fixed timing are a compromise
of sorts. The result of variable valve timing is better fuel economy
and/or more power, depending on how the system is tuned. I imagine
they are going for the "more MPG" tuning on the Elantra, but I happen
to think a little extra low-end torque wouldn't hurt.
Variable valve timing is one of the reasons a gas-powered 2003 Civic
gets 38 MPG highway while a gas-powered 2003 Elantra gets 33 MPG hwy.
There are other reasons, of course. For one, the Civic's engine has a
smaller displacement and generates less power. But the variable valve
timing is probably responsible for at least 3 MPG of that.
Hyundai's variable valve timing system is already on Elantras currently
being sold in Korea and I believe it is slated to appear on the 2004
models here in the US.