When I was driving fast food (Chinese, Pizza, Indian food, Greek) as my side gig, I kept a careful tally of tips and deliveries. My car didn't have a working odometer, so I couldn't factor fuel and mileage into the equation, and I know that I was robbing Peter to pay Paul. A few nights I gassed up at teh start/end of the night to see how much fuel I burned. I figure normal night was $15.
Average tip was around $3.00 IIRC.
Max deliveries per hour worked out to just over 3.5. Average was just over 2.5. By the time you fart around in the restaurant getting the food, and dink around at the door with the debit machine/making change, you are around 20 minutes per delivery.
A normal 8 hour night would see $3.00X2.5X8=$60, I could hit $80 with some regularity. I also hit $40 more often than I care to admit. Usually Mon-Weds.
A really good night would be 10 hours with multiple pickups at the restaurant for each trip, cutting the restaurant time down. In that scenario I could clear $120 in a night, but you had to have a lot of cards fall just right, and you were guaranteed to be delivering some cold food to some angry people.
I spent a lot of time hanging out in pizza place parking lots waiting for a call. Honestly, it was fun and social, and let me see a side of people I rarely see. I have no regrets even though as a moneymaker, it wasn't fantastic.