Depends what you mean by Lag-spike.
The most common types that I myself and others seem to experience here is: Connection Delay/Failure, Freezing, Low Frames and Stuttering.
What one would you say exactly is your issue.
I'd like to add also that rag-dolls do cause issues on both Client and Server due to their physics properties. Don't forget there are Enhanced Blood scripts on here and the Rag-doll is spawning slightly inside your vehicle do to the fact that the rag-doll completely replaces the person in this situation and spawns in place, up-right in a T Bone position and will then adjust to the environment around the rag-doll.
When rag-dolls are inside an object they act a bit frantically and cause issues with the game. There are also other lag factor issues that rag-dolls cause but the developers here seem to let that happen for the benefits that having intractable rag-dolls in the game.
