Armor never goes above 14, ramming strength never goes above 10. That said, a Klawstompa on the charge auto-penetrates each hit of his 8 attacks, gets +3 to any damage rolls and may then throw any wrecked vehicle across the board. The ram is not that special, all
apoc units are silly like that
Note that it usually takes more than one penetrating hit to kill any super heavy, including titans. You'd also be in melee range of the titan to simply stomp your ram if it survives.