SRI = Short Ram Intake
Short ram air intake - Wikipedia, the free encyclopedia
"A problem with short ram air intakes is that the air entering the intake is at a higher temperature due to the proximity of the engine, which can reduce performance. This may be partially offset by an increase in the volume of air entering the engine."
"A harmless but noticeable result of using a short ram air intake is an increase in intake noise, which may manifest as a sucking sound, and the loss of any silencing properties that the factory intake had."
CAI = Cold Air Intake
Cold air intake - Wikipedia, the free encyclopedia
"A cold air intake is a system used to bring down the temperature of the air going into a car for the purpose of increasing the power of the internal-combustion engine. Power may be lost at certain engine speeds, and gained at others. Because of the increased airflow and reduced covering, intake noise is usually increased. This effect is usually amplified on applications where a resonator, a part intended to reduce intake noise on some vehicles, is replaced by the intake."