My latest project, Twin OS Powered Tunnel

Well, here is a preview of my latest build, its a Power Surge Racing Products Nemesis .21 size tunnel. I had this extra hull laying around and decided to be creative and build a twin. I have always wanted a twin engine powered boat, and after seeing Mike Talley and Carl Van Houtens twin powered Shaman at the 2006 Tunnel Champs, I knew I had to have one. Initially I planned on using our signature series K&B 8907 water cooled outboard sport motors on the project, but made myself realize the limitations brought forth by a modified sport K&B motor. We really have pushed them to their limits in the horsepower department, and as a result started seeing failures with the engines, i.e. cracked cases were common, as well as finicky needles. Of course it was a nice challenge to make the 30 year old technology, run with and sometimes outrun the newer style OS sport engine, but ultimately I grew tired of all of the work needed to make a K&B fast, only to have it come apart after a few races. The decision was clear to me, OS would be the power plants for my 2007 fleet of tunnel boats, including the twin. OS makes very high quality equipment, and with the right props and slight adjustments, the motors are ballistic AND dependable. It was a no brainer, once I broke the ties I had with the old K&B's.... The great thing about the sport configuration twin is that it can be run in a number of classes including, Open Tunnel, Open offshore, Sport D (.45) Tunnel and Mod D (,45) Tunnel.




Here is a shot of the mount system. I tried to keep it really simple and utilize the stock mount system, and also make it work that when you adjust the height/angle on one engine the other receives the exact same adjustment.

Good side view, looks pretty tough with all of that power hanging off the back of the boat....

Good shot front he rear. You can see where I had to angle the carbs to get the stock needles to clear the other engine, I also added main needle extensions to make the adjustment a little easier. Not much clearance between the flywheel, but a little is all you need.

Right side view, gotta get rid of those Novarossi stickers....

One last rear shot, I extended the water "outlet" of the right engine to ensure no water gets sucked into the left engine while running...