Looks like the length has stayed the same at 18’8” but the width was reduced from 8’6” to 7’10” thus causing the hp reduction as you stated. The thing about that is Nitro knew what they were doing when they reduced the size of the boat. The Z18 is now most likely just under the needed requirements for a 200 hp motor. Just aggravating, i don’t like under powered boats. To be satisfied i would have to go with the Z20 with a 250, which i think is their goal.