Sure would be great wouldn't it? Bolt on a blower and add 42 mph to your boats top speed without a hitch. A simple weekend bolt-on project. Yeah, right! If you've done it, congratulations! I did pick up 42 mph, but it wasn't as trouble free as I would have hoped. Our boat started life with a 454 Magnum, carbureted engine running through a Bravo 1 swinging a 26 pitch Bravo 4-blade prop. Top speeds was 72 mph on GPS. The warranty ran out and then the "fun" began! First, IMCO Powerflow exhaust and a Holley carb. No real big change in speed, but better acceleration and an increase in mid range torque was obvious. Then after loosing a
coupling and having to pull the motor anyway, why not upgrade the motor a little bit? A B&M 250 supercharger was purchased. The engines shortblock was left stock with it's forged crank, rods and pistons. The heads were pulled and rebuilt by Larry's Speed & Marine in Tucson, AZ, adding Severe Duty intake valves and Inconel exhaust valves. Screw in studs, new valve springs, and a mild port job was added as well. The carbs were a pair of Teague modified 750 Holley's. Valve actuation was controlled by a Lunati roller cam and lifters. Ignition chores were the job of MSD. The increased fuel demand was the job of a Holley electric pump working with the stock seawater pump mounted mechanical pump. Dual ram external steering, by WPM was installed at this point by Bergeron Engineering in Mesa, AZ. Initial testing saw speeds in the mid to upper 90 mph hour range turning a Bravo 30 pitch 4-blade prop though the stock 1.50 gears.
Things went fine for the next season on the water! Then the day after Thanksgiving 2000, a trip was made to Saguaro Lake. After tearing up the lake with some other friends we noticed a high speed miss. Well obviously the rev limiter was the problem! (bad assumption) We yanked out the 6000 rpm chip and went on our merry way! As we rounded a bend in the lake at 90 mph we smelled something. Is that oil I smell? I pulled back on the throttle and the boat stalled. After finally getting the motor fired there was the ominous sound of rods knocking. Oh yeah, and the oil pressure (or lack there of) alarm was screaming. Damn, I've got some explaining to do now! Well, after a post engine tear down, it appeared that constant 6000+ rpm blasts were a bit much for the stock Chevy oiling system. We spun several bearings, heated the block and crank WAY up and luckily didn't toss a rod! What to do next?
