Try ebay for used tilt and trim.<br />Better to buy a new CMC unit like this:<br /><br /> http://www.iboats.com/mall/index.cgi?prod_id=13581¤t_category=cmc&cart_id=634081303 <br /><br />Starting with the 50 hp at the powerhead, minus 2-4 hp to get it to the prop, minus the possible 3-5hp from manufacturing variances, you will be down around 41-48hp. Now factor in the age and condition of the motor???<br /><br />You could be somewhere between 35 and 48 actual prop hp. Maybe even as low as 20 hp if it doesn't run worth a crap.<br /><br />Max rpm is for the motor, not the boat. You need to get the correct prop on the motor so that the motor reaches 4700-5500rpm at full throttle.<br /><br />If your rpm are over 5500, then you need to get a prop with more pitch. If the rpm are under 4700 rpm, then you need a prop with less (lower) pitch.<br /><br />Read this info here:<br /><br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=36;t=000015 <br /><br />And this:<br /><br /> http://www.boat-props.com/prop_rpms.html#1
