What do you mean? Like the cop cars in this video? It isn't a BNDL swap, I can't do those either. This is a good tutorial on how you can drive the cop cars if that is what you meant: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE--Zeze1GcBoE.html
The damage was like that for cop cars, like they had health. If you watch in pursuits, some go over a small bump or jump and just die entirely. I think it's to keep spawning fresh cop cars and get rid of older ones that have been in the pursuit for a long time