Audiofn

Slipping when? When you are getting on plane? When you are running at speed? Just because a 4 blade is slipping don't mean jack chit! Try different props. I know it is a PITA but just try stuff. You are in uncharted waters so you have no idea what is going to work best and the prop that will likely work best with this set up is what you think won't.

hotjava66

I agree, try everything prop wise that you can lay hands on. Dont count anything out. I have always wondered about CG on these hulls, may have a big role to play in how they ride. Mine will only porpise under 50, and then only if I trim out, rides perfect trimmed in. Once I get over 50 and trim out a bit, that is when the hull really shows its stuff. This hull works at speed, there have been a couple that ran over 100 at one time so you should be good once its figured out.

AIR TIME

The 4 blade slipped on plane with the bounce, and when getting on plane just as the bow came down and then bounced the most. if you could get that trans lifting prop sunday, I could meet you on monday or tuesday. I think one run with the 380s with all the props. and then pull off the shortie and try the standard lower. we will know then if its CG or drive. I should of used a little more tab last sunday. but that starter acting up pissed me off to much. since its to rich and loading up. a little porpoising is ok as long as you can stop it with a little tab. but the 1st weekend it was leaping out of the water the longer I ran it.

Audiofn

Have you been filling up the tank every time you go out? I am wondering if the bounce is getting better as you empty the tank?

mrv8outboard

The fuel load should not have a large effect on CG if the boat is set up correctly. It should just make it lighter as it empties. Other wise it is a problem that needs fixing!

KNOT-RIGHT

All good observations Jon!

At first thought. I agree one would think you are not in the usable range of the trim. However curing a boat that porpoises certainly requires a trim in. How can you trim it in if your already trimmed in. In other words "set the Hull" then come back and trim up.

The CG issue I crawled up in the forward bow way up and
added 180lbs to the nose. Equivalent to 4 sand bags?
According to captain Art it had now effect. By the way I was
Scared Sh@t have you ever gone for a ride with Art in a car
never mind a boat Anyway maybe two guys preferably gay
should go in the nose.

Right now that boat does not have the ability to carry the nose.

KNOT-RIGHT

Agreed 100%

How do you know where the cg should be?

In setting up my cat I just called Peter at Skater and he told me
dead center of the fuel tanks.

I have a friend right around the corner with a crane who has offered
to help. I,m thinking 8 inch pipe "pendulum" gently lowering find the balance and theres ya CG.

littledcsrodshop

iTrader: (1)

I hear you on not wanting to deal with the boat jumping around at low, or "cruising" speeds ect.. I set the X on my boat quite some time ago and put it at 17 3/4 (measured up the transom, at the transom) Not sure of the "exact" dimensions off the top of my head of an XR shaft to shaft but it seems to be just a touch over 21 3/4" I ofcourse have all that info at home but either way all & all my propshaft is just a touch deeper than 4".. Eventhough I knew I could easily go down with a simple spacer I didn't want to go crazy high..

I ofcourse built two 40 gal. saddle tanks that sit in my engine compartment, but will still have the ability to use my two 58 gal. tanks under the floor if need be and "center of gravity" is an infact issue..

However at the rate I'm going none of it's a real issue right now.. haha.. I wish I had some real world info for you, but since I don't I'll just say stick with it & keep good notes !!

The weather has been kinda nasty on & off here all week, but I plan on getting under mine over the weekend with a good straight edge & taking some good rocker measurements just to have, and would love to see a couple other guys do the same.. Not to derail the thread or get to much info going, but I would still like to know if all the bottoms from 87-97 are the same, or if the twin's & the single's were the same, also did anything change on the bottoms from boat #1 to #22 ect..ect.. ???? I know (weiland's) boat hull #1 was built originally with an arneson then later converted & your boat would have been the first "bravo boat" out of the mold, so just courious as to whether there was any bottom tweaking that went on back in them days... ???

Lastly I know my boat had to be the most azz heavy 28 they built considering it was a twin bbc boat with speedy #5's hanging off the back, and ofcourse tranny's inside.. I obviously have no idea how the boat handled at low speeds, and from what I know I'm not so sure anybody knew of it ever running "say" 30-60mph.. I still have the velcro wrist strap that was attached to the throttles, and I'm guessing again but I don't think JD had it in there for cruising..

Anyway's keep after it dude !!!

BGIII

iTrader: (3)

Boat #'s 1, 2 and 3 all had the original bottom for sure and I think they changed to the updated bottom starting with #4. #1 and #2 were singles and #3 was the first twin. I am not sure about any changes in strake placement or changes in the V portion of the bottom, but the very clear and noticeable difference between the old style and new is the width of the chines. The first few hulls had much narrower chines. They did have noticible lean in the turns and were not quite as stable while resting. I think this became most pronounced when they built the first twin engine 28 and that is what brought on the change, which at least consisted of widening the chines. There are a couple people that have owned both style hulls and I was told the old one rides a little better and the new one is a little more stable. Both are fine hulls, just different and both are desirable (to most, it seems). I do believe all boats made after the update are exactly the same hull dimensions.

Nauti Kitty

Bill has the whole story correct The ride difference was noticeable but the handeling difference was even more so.

NK