setback changes for the better

[silkeysak]

I modified my 7" jackplate Into 4" (can,still go back to 7" if I want). Ran it yesterday about even with the pad. Saw increase from 5000 rpm (very low), up to 5500, with an increase of 3mph, and definitely getting up higher on the pad. It seems that setback and motor height was my problem. Going to raise another 1" today hoping to get 6000 rpm and more speed increase. Getting the set up right on the Viking is taking some time. With less setback the handling is definitely better. It's hard to get a good gps reading because I'm always going with or against a pretty stong current with the high river and spring tides we're having now. I hoping to get it dialed in so I don't have to change stuff every time I go out. There has been some discussion on S&F about setback lately, but what I'm seeing is that on a Viking 4-5" works better than 7". JMO. I will try to get some more video tomorrow

[RussF]

I have a 4 on my Thunderstream ( VKing ) and in 1983 I also had a VKing with a 4 on it

[silkeysak]

Maybe you can help me RussF. I ran it yesterday, about an inch above the pad. The rpms came on up to 6000 like I wanted. The problem is, it starts to go into a propwalk occilation when you start getting into the throttle at high speed, and gets progressively worse until it wants to go into a full blown chinewalk. I am thinking that I don't have enough torque tab built into my skeg. What do you think? If I add more tab, will it help keep the lower unit from wanting to pivot up to the right, in the direction the prop is taking it? It seems like there is just not enough tab there to keep the lower unit locked in, if you understand what I'm saying. When I'm running 1 1/2" lower it tracks fine, but obviously there is more lower unit in the water for stability. I feel like I'm close to getting it right, and I hope it can be remedied by adding some more suface area to the tab. Help me out here, if you can. Thanks.

[RedDemon]

I just set my motor back from 10 to 13inch's on my 86 Valero and with a 30p chopper it will plane out in about 30ft and run 7200 rpm at 87mph. with it set at 10in I only got 6400 at 83 mph. The point of the cone is 1 3/4 in from the bottom of the boat. It still handles good at 10 or 13" back. Running solid mounts too help 100% with handling at high speeds.