Hello I tried signing up for UFPS Forum, but their site is going through some changes. Regardless… I have this advanced UFPS character parented to my vehicle that moves. When It’s parented it wont apply damage. Here is a vid where I discuss the problem: UFPS Turret Question - YouTube
I never used UFPS but I had experiences from the past with this.
Have you tried debuging what the raycast hits when your attached to the vehicle? See what it hits.
If it doesn’t hit the wall then you have to make sure that you raycast from a different layer, so that the collision doesn’t work with the car itself.