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Has anyone had experience with these? (Jack Plates). All the info I find on them doesnt really address the real benefit of one, other than they offset the motor back into cleaner water and make the motor supposedly perfom better. I know that this allows you to raise the motor up but if your transom is at the proper height why would you need a Jack Plate? Isnt this what Power trim and tilt does other than raiseing the motor up. I just purchased a used Hond BF45A four stroke for my Sea Caoster project (had one on my 16' Hewes craft Alum boat) liked it very well although a little heavy ran the boat fine. Thanks for all your thoughts and input. Jim Hays

Jim,

I have not had any exprence with a jack plate but I guess if you are looking at getting the most out of your motor and need to beat the other guys to the hot fishing spot then I could maybe investing the couple hundred $'s for one.
I also would questions there use on an older wood boats transom. I would think that placing the motor farther back from the transom is going to cause more torque to be exerted on the transom. When you increase the distance the motor is away from the transom it is like putting a pipe on a wrench handle to get more torque to break lose or tighten a nut or bolt.
Is going a mile per hour faster worth the cost of the jack plate. Anyway those are my thoughts on jack plates.

Good Luck!
Phill

Thanks Phill I dont really plan on putting one on I replaced my transom and added 2 knees to help support the extra weight of a 4stroke, and Im not interested in doing 100mph just wanted some thought about these. Being a novis at repairing a older boat I will have some different questions about things and will welcome all thoughts and opinions Jim Hays.

Jim,
Jack plates down here are for raising engine vertically for shallow water, ie bay fishing. I can't imagine the need for one on any wood boat of these styles. You are right if you have the correct transom/ engine match there is no need.

Jack Plates will:

1. Generally increase boat speed 1+ MPH ( in the 45 mph+ range) for each 1" motor is lifted till the prop venilates. With a good prop this could be 5".

2. Lifting the motor on a high perfrmance boat will generally inprove high speed stability.

3. Moving the engine back will also increase speed in a boat that needs bow lift. The farer back the plate, the more torque on the transom.

4. Raising the engine will also decrease draft in any boat.

5. Best when used in conjuction with power trim.

For most of our lapstrake wood boats the best benefit would be decrease draft.

Longer set backs would increase forque on transom.

Overall not much use for our boats.