The kv1 has 800hp however he is the only (if I am not mistaken) tank that gets a 20% damage reduction from the get-go. My question is are there exceptions, like arty? I tested mines however the damage of mines is also reduced.
If there is no exception then one could get the effective hp like this:
hp = 0,8 (normally 1) x d (incoming damage)
800 = 0,8 x d
d = 800/0,8
d = 1000
So the kv1 has effectively 1000 hp with the only difference that he needs less time to repair.
Correct me if I am wrong