Re: Removing Engine (suggestions/ideas)
I did a lot of mods to BBC 454 Mercs in the past. The cams with smaller lobe centerlines seemed to work well, but the Mercruser cams and *required* valve springs are at the top of the game. See if you can get a factory take out set from an engine shop from a fresh engine they are upgrading. <br /><br />We had very good luck installing the larger Merc cam, carb, and springs, ie: stock 502 Merc set into a 365 Merc/454cid at 500+ hp/tq with a performer rpm and ported oval port heads and after much experimentaion. With lots of torque down at 3k rpm, mpg/holeshot was good and topped out around 6500rpm. Ran even with Merc 525 Blower motor.<br /><br />If you do not want the hassle, go one step up from the standard Merc 350cid cam and get better performance with little trade-off. Maybe get a hipo 350cid Merc cam and put it in the 350 if you want to go fast. Pay attention to the valve bowl porting, quality valve train, and wet headers or at least elbows depending on how wild you get. High rpm automotive ideas like single plane intakes, big ports, and high rpm cams do not work well in normal boating applications. Focus on a flat torque curve with rpm matched components. The Merc parts are expensive new but worth it. I think Crane makes the cams. Most of the other parts can be used off the 305, but find out what hp your drive will handle, and change the Merc lube a lot to make it live. Never had a problem with the Merc ignition, water pumps, coolers, etc, at 500hp on a BBC. Just fuel and air flow components where changed. Stick an impeller in there too while apart.<br /><br />Did a 400cid GM with performer rpm intake, holley 750, good heads, and bigger exhaust with a 305 Comp cams that was too big; and it ran 74mph in a 19'. Original 305 had frozen up. Scary fast but it was bog city to get on plane and not good to idle/shift because of huge automotive cam. The guy beat his neighbor though, and that was all that mattered to him.
