Six Star Magazine Six Star Magazine Spring/Summer 2005 | Page 25
ACCESSORIES
get ready for fun
The computer controls hydraulic pressure entering a chamber
at the front of the intake camshaft that retards intake timing
as engine speed increases and creates more overlap (when
intake and exhaust valves are opened at the same time).
One of the advantages is that exhaust gases escaping into
the exhaust manifold actually draw intake gases into the
combustion chamber for the next combustion process.
The other part of the picture is valve lift (how far the valve
opens, which is a bit like opening a water tap a little or a
lot). At idle, the valves open less than at high speed, but
it’s a little more complicated than that. To achieve proper
combustion, we need to accelerate the air at low RPMs. This
is done by opening one of the two intake valves more than
the other, which creates both an imbalance of air entering
the combustion chamber and a swirl effect that properly
maintains air and fuel mixture for improved combustion
and fuel economy. At high RPMs, both valves open to the
maximum amount to allow maximum air flow and power.
To help make the most of your spring and summer adventures,
Subaru offers a wide range of accessories for our full lineup of
vehicles. Whether you need a bike rack for your Outback, a roof
cargo bin for your Forester or just a cargo net to keep things tidy
in your Impreza, all it takes is a visit to your local Subaru Dealer.
1
At Low Speed
Valve lift [mm]
2
Cam angle [deg]
3
4
The fact that each intake valve is opened a different amount creates a swirl effect
to better mix fuel and air, thus improving combustion, power and fuel economy.
At High Speed
Valve lift [mm]
5
6
Cam angle [deg]
1
2
3
4
5
6
Opening both valves to their maximum allows a greater air mass to enter the
combustion chamber, improving combustion efficiency and power.
Hitch mounted bike carrier
Roof cargo bin
Cargo area net
Dog guard
Wheel locks
Auto dimming rearview mirror
*Accessories may not be exactly as shown.
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