Have to agree somewhat with Spaw on this. I think it must have something to do with the fumes. High octane petrol, methanol, nitro-methane, burning rubber, hot metal etc. Although the finest of them all was the smell of Castrol R a mineral oil used in high performance motor cycle engines.

Some of my finest hours were spent on the startline between two dragsters being covered in noise and smell, both so tangible you could feel the noise and hear the smell. Ah! memories.