"Creative engineering" stories have always fascinated me. I have not really read too many from the drag racing world but one of my favorties was when fuel teams in the 60s were messing around with Hydrazine. From what I understand that stuff could blow up on its own if it sat in a fuel tank long enough. Well during its heyday there were a bunch of fuelers sitting in the staging lanes when someone went out and oiled the track pretty bad and all you saw in the staging lanes was a mad dash of several teams taking their tanks out of the dragsters, running over and dumping the contents in the grass and rocks next to the staging lanes. I think in the same article is was not uncommon for a dragster to make a run, get to the shutdown area and immediately see the driver dump what little was left over out in the grass as well.
On the NASCAR side of things, Darrell Waltrip was on Dale Jr's podcast several years ago and he went on for about 30 minutes about all of the "creative engineering" that went on when he was driving for Junior Johnson. Stuff like going through weigh-in with radios and helmets that each weighed 50 lbs. Having buckshot in the frame rails that the driver would open on the pace laps to shed extra weight. I think it was Junior Johnson that also used plastic or clay bolts on the back bumper of the car that when it hit a bump on the track it would break off and shed the bumper losing weight and helping with the aero. My all-time favorite was the great Smokey Yunick was getting torn down one time because his car had much better fuel mileage than anyone else by a huge margin. Well they pulled the fuel tank out of the car and were combing over every single inch on the inside and out. The official was scratching his head and could not find anything wrong and said he passed. Smokey laughed at him and before they put the fuel tank back on the car, he fired it up and drove it back to his shop in Daytona down the street from the track laughing and waving the whole time at the NASCAR officials. Of course now the inspector was even more stumped and baffled at what he was watching. Turns out Smokey had a fuel line that was an inch in diameter and coiled up to where he could hold an extra 3-4 gallons. At the time there was no rule on the diameter of the fuel line, only the size of the tank.