They're not necessarily 16 "different" sounds, just multiples of similar ones.
For example, if there are several cars close to you in a race, you'll hear
their engine sounds, tire squeal, etc. in addition to your own. Choosing 16
sounds just increases the number you can hear. Your own car might have 4-5
sounds playing at once; engine, wind noise, tire squeal, the rumble of outside
tires on dirt(!!), gear change, etc. While having more than 4-5 sounds adds to
the experience, it costs you FPS and doesn't help you go faster, so experiment
to find the combination you like best.
Steve B.
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