I decided to get a Jack plate for my boat. I'm not running a big hp motor, only 75Hp, but a little extra performance is never bad. My question is. I have been looking at JP and have found 2 different styles. I am not sure what one is better. Both are adjustable  6 inch setback with 4 inch travel. Made by the same CO. One is a one piece   and the other is a two piece. What is the big difference? i want to spend the least $$ like most people, but I want the best product. the one piece is about twice the price of the two piece. What one do you think would work the best for me. Remember I am only running 75HP

I have a CMC 6" adjustable jackplate I don't think I have found the sweet spot yet but I don't go hog wild trying to find it when I go out I'll adjust the motor up 1/4" leave it there for the trip so far the big difference I have found is that I don't loose as much mph when I have 2 or three people on board but have not seen a gain with myself only on board but have not lost anything either. I have a 90hp Merc on a 17' Tracker Targa Deep V or as they call them in the far north a Walleye boat.

http://www.cook-mfg.com

Chow

First check to see if the boat can handle a plate and if it doesnt void any warranty. Then  as you say you dont need  overkill. A 2 pice will get the job done and weight the least. A 1 piece is a bit stronger but has some added weigth.  6" is about the most you would want and be sure all the cable especially the steering vable will strech back that far.  

TH Marine make one for about $175.00 and  there is always a vance brand on ebay for mid $150.00.

Only dealing with 75 hp most any will work.  How hard they are to adjust is the thing you want to look for.  Can it be adjusted from inside the boat or do you have to put it on the trailer or get out in the water to loosen bolts to adjust it.  Usually the cheaper they are the more of a pain in the butt they are to adjust.

The size is determined by the boat manufactors warrenty (some don't allow any, those that do have a limit) and the amount of built in set back.   About the most I've been able to put on a boat without changing out steering/control cables is 6 inches and even then it has them in a pretty hard bend.  I've had some that I couldn't even get that much without changing the cables

Detwiler and Right Height  are two very strong units but probably a little heavier than you need, you can pick good used ones up for $150 or so.

Thanks guys, any more info would be great.

I think the one piece would be easier to adjust, just one nut instead of two.

I am not worried about a warranty. The boat is 17 years old. and out of warranty

Just as Pa angler said and has is a deep V. a  Sea Nymph GLS 175  17 1/2 foot. The cables will reach. I had new ones put on 3 years ago and they are a little long so there is a nice sag in them as they run down the side of the boat. The boat and transom are in great shape. the transom is rock solid

I wasn't sure if I was going to put one on. well I blew up my motor. a 75Hp suzuki. then I found a used 75 suzuki  the same year as mine. Took my motor off and went to put the new one on. well the bolt pattern does not line up. I thought they are all standard? The motor I bought was one of a pair of twins. I guess the mounts are narrower on twins. The holes are off by 1/2 inch. I would much rather buy a JP and drill new holes in it, than drill 4 new holes in my transom