Below you'll see the aft deck and transom of a Boston Whaler REVENGE 22 that was probably originally a Sea Drive model. I believe the Sea Drive was removed and the transom repaired. An Armstrong aluminum engine set back bracket was installed. This particular bracket is quite a long set back. I don't recall the exact dimensions, but as seen below, it is a generous set back distance. An OUTRAGE 18 with a closed transom would look very similar to this, although the beam of the boat would be smaller. The Armstrong brackets are usually custom-fabricated and expensive. I don't know exactly how you go about calculating how high to mount the bracket on the hull. I think Armstrong gives you advice on that, as they have obviously got a lot of history on how to install their products.
The transom of the classic Whaler hull is not completely flat, as you can see here. The center portion is usually thicker by about an inch. With the transom closed, there must be some way for cockpit water to drain quickly. In the Whaler Drive configuration, two large, about 3-inch ID tubes are cut through the transom so the bottom of the tubes is level with the deck. These two large openings will drain the cockpit to the sea if a big wave comes into the cockpit. Normally you don't even notice these drains because their outlet openings are hidden by the wings of the Whaler Drive. The wings of the Whaler Drive are not flush to the transom, so there is about a one or two inch gap between the drain outlet that is flush with the transom and the wing of the Whaler Drive.
In the modified boat seen below, you can see a through-hull drain exhaust on the starboard side about a foot above the water line. I suspect that is the outlet for a sump pump that is intended to get water out of the aft cockpit area that is under the rear deck.
The boat shown was a good performer and seemed to ride very nicely. This boat was owned by Don J. at the time, and I don't think we ever had a flat out race between that boat and my very similar REVENGE 22 W-T Whaler Drive boat (also with a 225-HP). I would not have been surprised if Don's boat was a few MPH faster at full-throttle because the Anderson bracket would have been running mostly clear of the water.
- Boston Whaler REVENGE 22 W-T with Armstrong Bracket
- closedTransomWithArmstrongBracket.jpg (31.87 KiB) Viewed 16381 times
The anti-fouling paint water line seemed to be applied a bit high on the boat and assumed a static trim that was down by the stern. In this picture, the boat is in a lock and the crew is standing at the bow to handle a line. This results in the stern sitting a bit higher than it probably would at rest with no one aboard. The Anderson brackets do not provide as much floatation as the Whaler Drive does.
For comparison, I include a view of the same model boat, REVENGE 22 W-T, with a Whaler Drive. You can see that with only a single engine on a Whaler Drive--which was often though to be intended for twin engines--the static trim at the transom is quite high. The transom splash well drains are well above the static water line. Again, in this view, there is crew on the foredeck to handle a line, so the stern is a bit higher than normal. You can also see the wings and the gap to the transom, where the cockpit drains are concealed.
- Boston Whaler REVENGE 22 W-T Whaler Drive
- whalerDriveTransom.jpg (33.65 KiB) Viewed 16381 times
In both these views you see how close to the surface of the water the anti-ventilation plate of the outboard is sitting.