Here we see that the Evo 3 intake port flows better than the Evo 3 exhaust port (the same is true for the 215 HP head).
This is to be expected as the pressure driving exhaust gases out of the cylinder is quite high,
so exhaust port flow need not be as great.
The exhaust port starts to "choke-off" a bit sooner than the intake port. This is possibly one reason
why it is not necessary to run as much lift on the exhaust side of an S14 cyl. head as on the intake side.
Most of the popular cam combinations for this engine are staggered, with the intake cam having
greater lift/duration than the exhaust cam (i.e. the Schrick 284/276 pairing). This chart shows
that having as much lift on the exhaust side of an Evo 3 head as on the intake side would not
yield additional exhaust flow. But due to the greater pressure pushing the exhaust gases out
(relative to the intake side) the exhaust ports flow well enough to keep up with the intake side
even with lower lift/duration.
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