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View Full Version : Height of pad? What effect does it have?



sho305
10-14-2002, 11:03 AM
Thinking of putting a pad on my 17' Checkmate, and am told to try 8" wide by 8' long like a 'Stream. On my 16' Bayliner, it has 8-9" wide pad and it tapers smaller up to the bow at about 2" there, and maybe 6-7" in the center of the boat. However, it is flush with the bottom, like the vee was cut off. It handles well considering what it is.

My question is what would happen if I screwed a 2" thick board on there to make the pad higher/thicker like I see often? How would that affect the boat? What if I stopped it 10" from the transom, in effect relieving it? Considering the 40mph of this boat, would it have to be wider to get it up on there? Would I have too high a drive then? I raised the motor .5" when I did the transom, now the cav plate is a fuzz above the bottom when level. It runs trimmed up quite a bit, and may have a slight .25-.5" hook about 4' from transom from the trailer bunks. The high trim is limited by the porpoising before it will blow out. Would I have to put a slight vee in the pad, or side strakes on it if I did this? I am assuming it would have to be the same width all the way if it protrudes from the hull unlike it being flat now.

I can screw with this boat, just thinking of trying some stuff before getting into a major project. Have no pics of mine yet; but this one is for sale and is the same hull and motor as mine: http://www.iboats.com/boats/marine--1/boats--10/powerboats_to_35_ft--100/bow_riders--1004/10681-ad.html

If you enlarge the pic, you can sort of see how the bottom is flat under the drain plug.

175checkmate
10-14-2002, 03:42 PM
I am going to do the same thing this weekend. Going to indstall a temp pad for now and do some testing. Looking at the bottom of some of the streams and allisons. I am going to make the pad high enough, so when riding on it the rest of the boat will be out. Not sure how high that will be yet.

sho305
10-15-2002, 08:51 AM
Every one I look at seems to be 1-2". But most have a slight vee and are wider except the real hardcore speed boats. I think this reduces chine walking, but the vee loses lift so it is wider. I am guessing higher is faster, but again at the expense of poorer handling as you have the boat balancing higher in the air. It obviously looks like the relief is like setback for the motor, but then you are shortening the hull in essence, and reducing rough water ability, so setback might be better although it is a pain and expensive.

Also makes sense that the width will dictate what speed it will come up at depending on boat weight/power you have. I have been researching it, and while the original 'Streams are some of the fastest, they take some real butt-glue and white knuckles to run if not setup perfectly. Go to the STV page and read the driving tips, and that is for a tunnel! They have a very nice walk-through:)

Here where I run, I encounter rough water all the time(min 1" chop, 2' wakes, in big lakes). So I am not liking the idea of all out speed as I will never be able to use it. Nobody talks about running 70-80mph and encountering 2' wakes (from all the I/O vee hulls here pulling tubes) at an angle! I think the newer designs are slower but more managable and usable here. On my little lake here I am getting the whole boat out of the water at only 50mph with a straight vee. I do have to have the trim up to get over 50, but the bow is not that high. Maybe I need to go to 18'?

With the Bayliner I just thought it would be easy to screw something on there to get a feel for what I need for the Checkmate. I don't care about a few extra holes in that, it would make it stronger I think and I have some epoxy left over. Not sure if I can even get it up on a pad at 40mph though, and I'm not gonna change the motor. Sadly it froze here this week, so I had to winterize everything. Might get going on it this winter after I decide what to try. Thinking of a wider pad, maybe 10-12" with a slight vee and stop it 6-8" from the transom. This might float the Bayliner at 40mph, and it might even go faster! May also put some ventilating cuts in there for fun.

sho305
10-16-2002, 09:48 AM
Have another thing to think about. Read about this place adding step pads to big boats, Bobby Moore.
http://www.boats.com/content/default_detail.jsp?contentid=2045

Check out Regal boats: http://www.regalboats.com/viewBoat/index.cfm?fa=viewBoat&boat_id=44

Bayliner has one too and many of the big offshore hulls are going this way. Getting good reviews on this too. Wonder if steps can help speed while still keeping rough water abilities instead of going to a full speed pad. They still use a pad anyway with the steps. Gonna be a choppin' on the bottom anyway, only some more work to do...these manufacturers are researching this and got to know something since Hydrostream 30 years ago? Given they are not out for all-out speed, but hey I got waves to go over here.

Any opinions on this??????:) :confused: :eek: :cool:

vector mike
10-21-2002, 09:09 AM
If wave jumping is what you are going to be doing most , than a flat pad is not the way to go. The pad deffinately does make for a harder ride. If you are not into the 60's with your boat a pad is pretty much worthless anyways as would be a nosecone. You need to decide what you really are wanting, a fast hull or one that rides smooth in the waves. :)

sho305
10-21-2002, 09:33 AM
What I am thinking here, is I will be running on lakes mostly, and not protected rivers, etc. I will have up to 1' chop and occational up to maybe 1.5' wakes to contend with from other boats. Not worried about running Lake Michigan unless it is calm. I will not worry about full speed when it is rough, but I don't want a hull that is useless in less than perfect conditions either as I will seldom see glass water.

I would like to stay around 17-18' for easy handling/launching, and go min 60-70mph, maybe faster later. Thinking 200hp max right now as I have to buy a house too.:) Airing the boat a little can be fun, but about flying out is not. Not into that anymore...

I prefer a BR for the room, but not mandatory. Not sure I'll have the time now to do the Checkmate, so I might be shopping soon for a used something. Any ideas would be appreciated!