You want 102.4% combat table coverage to avoid unblocked hits (we avoid crits through talents). It's block+dodge+parry+5% (for miss). It's 102.4% not 100% because we are fighting L88 foes. Use this macro to check it:
I think you mean you have 51% block and 14% dodge, rather than vice versa. Your numbers sound ok and will go up as you gear up. Many top palatanks are not yet block capped, so don't stress - it does require good gear unless you want to make big sacrifices elsewhere.
/script DEFAULT_CHAT_FRAME:AddMessage("Need 102.4 combat table coverage to be capped. Currently at: "..string.format("%.2f", GetDodgeChance()+GetBlockChance()+GetParryChance()+5))