this maybe wrong forum for repower talk, but here goes. stats, old (70's) 15ft cobia hull @ 1300lbs (yes i weighed it), presently 87' 48spl Johnson, cruise about 20mph @4200. looking at 40, 50 or 60 merc. am surprised at weight of hull, thoughts on if a 40 would due, maybe with command thrust option. have been on the Evinrude/Johnson forum for awhile but making switch to 4 stroke, loosing faith in the old Johnson after 2 tow ins.