Currently, a Lambo V12 swap costs the same amount of Car Points as Honda’s K20 engine. Instead of locking Engine Swaps, and really all parts, behind Car Levels, you should just increase their prices. Those prices should be proportional to these aspects of the engine: power, displacement, manufacturer, real life availability. Proportionally to other Upgrade costs, the cheapest swaps shouldn’t exceed 1500 Car Points, and proportionaly the 26B from the Mazda 787B should drain you from Car Points by costing eg. 20000 Car Points.
In order to allow for other Upgrades to be installed with this Swap, the total Car Point count for a single car should be increased from 20000 to at least 30000. I also believe that this would require a big change to the Car Point distribution rates, because for now it’s just miserably slow. I would love to see CP earn rates of 400 for the first 40 Levels, then 1000 for the last 10 until Level 50.
I also think this would work amazing with another one of my suggestions, combining Car Points across one/all Manufacturers after achieving a certain goal