The engine builder said he will look back and see what all parts he used when building this engine. He said he does know it is a roller cam and roller rocker engine. The owner said he had to order a different intake to use a carburetor. So does this mean it is a vortec engine they put a carburetor on?

That's an impossible question to answer without knowing more about the engine itself and the history of the boat.

Unless I'm confused, I believe you mentioned that the engine was rebuilt because it was out of the boat, nothing was found to be wrong with it but it was rebuilt anyway. That would mean that if it were the original, then it would be a MK IV either 330 or 365 (Magnum). The MK IV was not a roller engine. Now, if the engine had been replaced sometime in the boat's lifetime, it could have been replaced with a Gen 6 and that would be a factory roller engine.

Again, hard to say what it could be.

There's an easy way to figure out GM's original intent of the engine's build/purpose, and that's by finding the code stamped on a pad on the front of the block above the timing cover. You can reference the codes at this link:

http://www.1968ss.com/bbcsuffix.asp

That'll give you a base to go by.

Here is a link to the Mercruiser "block decoder ring"

http://www.marinemechanic.com/merc/d...lockcodes1.pdf

The outdrive was rebuilt because it was out, the engine was pulled due to burning oil so they built a newer engine for it that is a roller motor. I asked him to get me the build sheet on it and send some more pictures and the block numbers. The engine builder is supposedly one of the best guys around the chattanooga area.

That's the one I was looking for originally! Thanks!

The only thing I'm not a fan of on the Atlanta boat is the exhaust tip exit. If you buy the boat, I would take those things off, and replace with deck plates. Coming off plane (or reversing), a TON of water makes it into that area and can get pushed up into the engine's exhaust if the internal flappers are bad (they usually are). That's a good way to ruin a nice engine! Other than that, she looks like a fine boat!

I agree tom. I really want to get rid of the silent thuder all together. It has its advantages of a place to set the cooler while out swimming. I have never heard one in person with the silent thunder. Only heard them with straight exhaust.

If you want to see what a teak swim step looks like on the boat look through the "Formula Flat Glass" section or check out the factory brochures on Formula's Vintage section, pre '86 will be teak platforms.

The red boat had teak. I loved it just don't know what to do with exhaust if I wove the silent thunder

I ditched mine because of the weight over the stern, and because it was a bottleneck for the exhaust. With the platform removed she rides better, and the engine is more responsive. Yes, I lost the "swim-up bar," and some people say she doesn't look right without it, but for me I like that it's gone. I do plan to put a tubular platform on it next summer.

Here's a video of mine running on the hose but with the plugs out of the Silent Thunder box:

http://vid216.photobucket.com/albums/cc38/zellto1971/1989%20Formula%20242LS/IMG_0380_zpsaro3o7tv.mp4