My 4200 V8 of course, with Larini, down shifting blips along narrow dry stone walled country roads with the windows open.
My Stag V8 of course, I've enjoyed that for 33 years so far, even had people follow me home due to the exhaust waffles, like the piped Piper!
My BMW B58 straight six, so smooth, so much torque, and a wonderful cold start bark when pushing the start button. A nice start to the day for a daily driver.
Then looking back, it wound have to be my old Alfa 33P4. Quad cam boxer with straight through autodelta exhaust!
Then not strictly mine, but my Dad's Honda Civic VTEC. One of the first in the country around 1990 ish. That VTEC on cam scream to 8K was addictive. Loved borrowing that car in my early 20's!