YOu are right about the difficulties in associating horsepower with thrust. Piston engines are basically power producing engines, that is the power they can produce varies closely with the fule flow. Jet engines are thrust producing, the thrust varies with fuel flow.
As the Power is directly proportional to the thrust multiplied by the velocity, a jet on the runway, on brakes at full thrust is not producing any power at all! For a better comparison, look at the results achieved:
A standard production V8 will do the quarter (mile) in about 16 seconds or so. That's 1320 feet, or about the distance required to get a 737 with two 20,000lb engines airbourne.
The production car weighs about 2000kg and finishes the quarter at around 150 kph.
The 737 will weigh around 55,000kg, and finishes the quarter at around 130 kn (240 kph) in about 12 seconds. (NB These figures are educated guesses.)
So tell your mate to imagine sitting at the lights next to a road train (ie a semi trailer with a couple of extra trailers on the back) in his road car, and being creamed in a burn off the lights ...
Tell him that during take-off, the 737 would consume the contents of his 60 litre petrol tank (converting it to power) in around 30 seconds!