Strut distance from transom

[Gary]

I always have had an issue with "prop hop" on my 29" hydro Saw boat.So I was looking at the distance from the back of the transom to the prop and its about 3 inches with the strut i use. Could this be giving more leverage to lift the rear of the boat. I have seen struts as long as mine and i have seen them very short if not under the boat. Is it worth experimenting or a waist of time.Is there a "normal" distance?Thanks.

[TRUCKPULL]

Gary

Strut length - whatever works for your setup.

Prop hop can be caused by many different things.

- Not enough lift in the prop, Boat just barely lifts then falls back in the water

- Too much lift, hops right out of the water then falls back in.

- COG is wrong.- Not enough weight on the prop.

- Thrust angle will make a big difference also.

Larry

[Gary]

Thanks Truckpull. I new about everything else but as I was looking at the strut setup I thought that a longer strut would create more lift because of the leverage it has.When i put a small scale under the prop and then moved it further forward the weight to lift the transsom would change by a few ounces.Could be wrong in my thinking, who knows.

[BILL OXIDEAN]

Thanks Truckpull. I new about everything else but as I was looking at the strut setup I thought that a longer strut would create more lift because of the leverage it has.When i put a small scale under the prop and then moved it further forward the weight to lift the transsom would change by a few ounces.Could be wrong in my thinking, who knows.

Generally any leverage created by strut length affects the front of the boat, on monos in rare cases a long strut will raise the bow, but in most cases a farther set back strut will give the boat more triangulation keeping the bow (or sponsons) more planted.

[Jesse J]

I have learned that the strut depth is a controlling factor on prop-hop. that is how my hydro in my avatar is actually flying in that shot. I dropped the strut some, it was more planted, but I lost speed. In ovals, you ride the fine line between too much hop and too wet of a turn. You notice she settles right into the turns? So if yours is hopping and you are only doing saws, you may play with the depth to see what may happen.

I don't see how angle affects the stern, I have found that the angle has more control on the bow than the stern.

[Gary]

There lies the problem. If i run the strut deep, it will run faster but be difficult to get the run started. Raise the strut and problem is gone but boat slows down. Also remember this boat makes so much power i can be going say 40mph ,,punch it and the boat comes out of the water and flips over. Very tempermantal.

[Jesse J]

Try a little bow down (not ) but angle the strut so that the nose of the strut is slightly up - this will force the bow down and slightly lift the rear.

Also, where is your COG? should be no more than 1" to 1 1/2" back from sponsons trailing edge. I have also seen guys run it farther forward - even in front of trailing edge... So it is very model/application specific.

It is odd that lower strut means more trouble to get out of the hole (if I understand correctly). Usually deeper means easier at least in my experience.

[BILL OXIDEAN]

[QUOTE=Gary;161244 Also remember this boat makes so much power i can be going say 40mph ,,punch it and the boat comes out of the water and flips over. Very tempermantal.[/QUOTE]

Wow!!

[Gary]

Its unreal Bill. I have to program in a very slow throttle slope on the hydra and add a slow curve on my radio. I really hope to be at least 106-108mph this weekend but keeping it in the water is really hard and my "room for error" is zero in my opinion because the damage from the wrong adjustment is always bad.

[BILL OXIDEAN]

Its unreal Bill. I have to program in a very slow throttle slope on the hydra and add a slow curve on my radio. I really hope to be at least 106-108mph this weekend but keeping it in the water is really hard and my "room for error" is zero in my opinion because the damage from the wrong adjustment is always bad.

You gonna' be shoootin' traps pal? Or are you gettin gps'd If you're shooting traps, where? I missed another SAWS event

[Simon.O.]

You gonna' be shoootin' traps pal? Or are you gettin gps'd If you're shooting traps, where? I missed another SAWS event

I'm watching this one

The way I see it, if you are up in the 100mph area you normally do not ask this type of question. I am yet to bang 70 ( I'm close) and can understand and quantify all the above answers.

If you are shooting at 100 and over, you should really know your boat and setup.

Flames do not bother me

[Gary]

Well.......the way i see it ........if you, myself , put a boat togather and the strut you use has always been the same for years, i was told that having a long strut is best because the boat will "think its longer" and perform better {perform better on the top end}.......and never gave it a second thought, then i guess this is why i asked the question. After running the boat and always changing props, strut angles, sponson angles,shifting weight everywhere i never gave the strut a second thought as to how much "leverage" it was providing on the transom. When you have a boat going that fast, in my opinion no question is inapropriate because i am no expert....just a hobbiest. I will ask as many people as possible about any change i make because at these speeds the boat self destructs at impact and it becomes very disheartining to say the least. Sorry for waisting anyones time. Bill..........i run an Eagle tree and an onboard gps on my boat. I take a two way average and arive at my number.sometimes with extra people i will have them shoot it with a radar gun as well so with 3 inputs i think im on the money as far as accuracy but who knows. Its a fun chase and i love doing it, but i do not compete.