The point of the mod is to make failure more realistic. In real life your car is often disabled in rather low speed accidents.
If you feel the car is too easily damaged, you can change one or two numbers at the top of the client.lua file:
local damageFactor = 15.0
local cascadingFailureSpeedFactor = 10
Try setting damageFactor to a lower number to make the cars more resilient to crashes.
The cascadingFailureSpeedFactor determines how fast the engine will self-destruct when the vehicle health drops below a certain point. Lowering this number will make the car work for a longer time, even after being badly damaged.
Think of it this way:
You can damage the car somewhat and it will still be drivable. But when the oil starts leaking, the car will self-destruct no matter what. It’s just a matter of time.
The first variable determines how fast you reach the oil-leak point.
The second variable determines how fast the oil will leak.
Remember to restart the script after editing!