Twin 318's Prop Help

[CaptDJ]

Have talk to 6 different prop guys and have gotten 6 different solutions. I have a '32 Luhrs Sportfisher fiberglass hull that weights 14,000. It has twin Chrysler 318's, 240 hp at 4400 rpm. 2.09 to 1 ratio, current max. rpm is 2400 and still have throttle left can not get on plane. Current props are 18/21 three blade props. Any HELP????<br /><br />Thanks,<br />Capt. DJ

 

[Silvertip]

Re: Twin 318's Prop Help

So what are the six different solutions you were given? Seems that when a boat doesn't perform the finger immediately gets pointed at the props when it can be any number of other things. First, how can you have a maximum of 2400 rpm and still have throttle left? Either the throttle is wide open or it'snot. If you have more throttle, use it. Next question is did the vessel ever plane under your ownership? If it did, something has obviously happened that is not prop related. Such as either or both of the engines are in need of work or if this is a saltwater boat, the hull may be bottom fowled. Have you added additional equipment? Is there more water in the bilge than normal. Are the water/holding tanks full. All of these questions deal with weight distribution. You have a very stern heavy vessel so perhaps you need trim tabs -- and if you already have them, are not using them properly. Talk with owners of same/similar vessels to see what their performance is.