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ken226

Bought a 2000 Chaparral 200 SSE with no engine or drive

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I know some of you guys are knocking the choice of a car engine, but from what I know about gm motors, the L98 would be a great boat engine. What '80s cars lacked in horsepower, they made up for in torque. The L98 was never a killer on the quarter mile, but from what I hear, they were unbeatable in the eighth mile (from it's low end torque). I think with a few modifications, this will be a great boat motor. I mean let's face it, most mercruiser engines are just Chevrolet truck and car engines. Check out the valve train specs for an LS1 Corvette motor and then look at the specs for a merc 350 mag. You might be surprised by the similarities. I'm excited to see how this is going to work out!

You may be surprised to find out that Mercury Marine actually made some of the really hot engines for Chevy back in the 70's, 80's and 90's. Ones in the Vette, especially. Usually the 4 bolt main engines.

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You may be surprised to find out that Mercury Marine actually made some of the really hot engines for Chevy back in the 70's, 80's and 90's. Ones in the Vette, especially. Usually the 4 bolt main engines.

Engine and drive are both installed and running. Here are pics of the engine idling on the muffs:

DSC06370.jpg?t=1297472852

DSC06371.jpg?t=1297472959

The prop is a 14 1/2 inch 26 pitch stainless Evinrude Raker II, I bought it before I realized Evinrude doesn't make a hub kit for a Volvo SX.

I decided to go ahead and use it instead of buying another prop, so I fired up my lathe and vertical mill and fabricated another spline sleeve, with the right offset, and milled a Torq-Flo nylon bushing to fit the Raker II. Its mounted up, nice and tight and turns perfectly. I guess i'll see how it goes sunday.

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It looks great. What is that at the end of the crankshaft? I don't recall ever seeing anyhting like it there. Hy

No kidding huh? That is weird looking. I'm no boat tech, but I have been an auto tech all my life and that just don't look right.

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No kidding huh? That is weird looking. I'm no boat tech, but I have been an auto tech all my life and that just don't look right.

The K&N is definitely a flame arrestor, even has the coast guard approval stamped into the rim of the lid. The thing on the crank is a raw water pump, volvo pentas don't have internal pumps.

I just put it in the water for the first time this evening, had really good results i think. I'm a boating novice, so it took me a while to figure everything out.

Everything started and ran great, but when i first started to accelerate, the stern sunk way down low and the front pointed way up, kinda scared me. Then i realized that i still had the drive unit trimmed up. When I trimmed it all the way down and gave it some gas, it jumped on plane in about 3-4 seconds, way quicker than the last boat i was in. I didn't have a GPS, but the speedometer hit 45 really fast, then took awhile to go up higher. Topped out at about 48 i think.

At 45, it was 4000rpm, I think this engine is supposed to redline at 5500, so it may be overpropped. Its a 1.85 ratio with 14 1/2 26 pitch.

I'm doing more research and seeing that for top speed you have to trim the drive after your on plane? It might explain why it feels overpropped, I had it trimmed all the way down and left it there, maybe it was "plowing" a little. Would running it trimmed all the way down slow the boat down?

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First, awesome job bringing a boat back from a sure demise of sitting on the ground!! I would love to have your skills.:beer-7687-1:

When I was reading your post and saw a 26 pitch prop the first thing that hit me was WAY too much. However, if you have the HP to turn it maybe it is only a little too much. I've seen that prop mainly on 225-250 hp outboards on bass boats. It will make them scream at over 70 mph. But that's a very different hull from what you have. A lower pitch will also reduce your time to get on plane. There are plenty of threads on how to find the right prop and they all say "grab 3-4 and see which one does what you want it too".

Yes, trimming up will increase your speed and smooth out the ride in most water conditions. You will know when you've trimmed up to far when the bow starts bouncing up and down (called porpoising). You will also get a small increase in mph and rpm.

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The K&N is definitely a flame arrestor, even has the coast guard approval stamped into the rim of the lid. The thing on the crank is a raw water pump, volvo pentas don't have internal pumps.

I just put it in the water for the first time this evening, had really good results i think. I'm a boating novice, so it took me a while to figure everything out.

Everything started and ran great, but when i first started to accelerate, the stern sunk way down low and the front pointed way up, kinda scared me. Then i realized that i still had the drive unit trimmed up. When I trimmed it all the way down and gave it some gas, it jumped on plane in about 3-4 seconds, way quicker than the last boat i was in. I didn't have a GPS, but the speedometer hit 45 really fast, then took awhile to go up higher. Topped out at about 48 i think.

At 45, it was 4000rpm, I think this engine is supposed to redline at 5500, so it may be overpropped. Its a 1.85 ratio with 14 1/2 26 pitch.

I'm doing more research and seeing that for top speed you have to trim the drive after your on plane? It might explain why it feels overpropped, I had it trimmed all the way down and left it there, maybe it was "plowing" a little. Would running it trimmed all the way down slow the boat down?

At roughly 2500 - 3000 rpm, raise unit slightly to find the sweet spot. You will know and feel when your there. Step two, WOT and hope you have enough fuel to get home. LOL.

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At roughly 2500 - 3000 rpm, raise unit slightly to find the sweet spot. You will know and feel when your there. Step two, WOT and hope you have enough fuel to get home. LOL.

Ok, I spent all day at the lake so i have a really good idea now of what will do. The best I could do with good trim is 52mph, as per my GPS, at 4200 rpm. My engine should be making peak horsepower at about 4900-5000rpm, so I need to try a 24 or 25 pitch, i'm leaning toward the 24.

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Find a good prop shop. Some will let you try different props or recommend one and switch it for another if it does not work for you.

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I put a 14 x 23 aluminum on it and didn't like it at all. The top speed was the same, 51mph according to my gps, but it took longer to get there, and was at 5600 rpm at 51mph. I could definitely feel more slip when accelerating, and it seemed more sensitive to the trim setting. Once close to top speed, the sweet spot for the trim was alot narrower. It just didn't feel like it had the "traction" that the raker 2 had.

Im going to try a tempest plus 14 5/8 x 23 stainless. It has alot more cupping and is built more like the raker 2 I had before. I'll report back after testing with the tempest plus.

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I did a lake test with my new 23 pitch Tempest Plus yesterday. With the drive all the way down it hit 51mph at 4700rpm, trimmed out it got 55mph at 5200 rpm. I'm happy with that, though i could probably get more speed with a 24 pitch. When we did the lake test, it was me and a friend, and half a tank of gas, so pretty lightly loaded. I think with a heavier load a 24 pitch would be too much, so i think i'll keep the 23.

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Cool, sounds like you've dialed it in. How was the acceleration?

The acceleration is awesome, but it was great with the 26 pitch prop too.

If I punch it from a dead stop it planes at about the 4 second mark, and hits about 50mph at about the 10 second mark. From 50 I have to start trimming to get up to 55, then I have to get out of the throttle because I run out of lake. The only like close to me is Patagonia, its about 300 acres, and half of it is no wake zone.

I might be able to get more speed out of it on a bigger lake, but it seems to be running out of steam about the same time i run out of lake.

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