Finally got around to putting the new exhaust on the boat. For the most part things went smoothly. My boat has silent thunder exhaust on so I thought there woulden't be any problem matching things up. Wrong! The spacing on the exhaust where passes through the transom is about 2" narrower than the center spacing on the new risers. I have the long SS risers and that left about 4" space between end of the riser and thflange at the transom. I had to get some new 4" exhaust hose as what I had was too stiff to bend. With plenty of lube (dish washing detergent) I managed to get things in place, clamped and bolted down. It looks good and is a little louder than the Mercruiser. I guess the long lengths of the original exh. hose quieted things down a bit. In hindsight I should have ordered the shorter risers it would have made things a little easier.
EMI exhaust system
- Thread starter 206LSdrvr
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Any pics. Thanks for posting your experience, might help someone out in the future! 
I'll make some pictures tomorrow and post them. One thing I didn't mention is the flange on the starboard side at the transom is about 3/4" higher than on the port side to clear the hydraulic steering assembly. Fun and games. All the brackets for the shifter, oil filter and the ignition module fit perfectly. Did have to go to a smaller oil filter.
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Lookin' good, I had some trouble installing Stainless Marine manifolds, interference with the power steering pump.
355 C.I. 4 bolt main block, Crane 109821 cam, World Sportsman II heads with 2.02 intake and 1.60 exh. valves. The intake manifold is a Holly high rise. Carb is a Edelbrock 1410 750 cfm marine carb. The flame arrestor is K & N. Estimated HP is around 360 according to Desktop Dyno. I've probably put between 100 and 150 hours on ti now and it has not missed a beat.