Question about extending centerboards

I have a Hobie 18 that is on steroids. I am running a Tiger mast with a large square top and a self tacking jib. I would like to hear from those who know about foils if there would be an advantage, disadvantage, or no change if my dagger boards were the same shape but a foot or so longer. Would the boat point higher? Would she go slower because of the increased wetted surface.

Better shape, lighter weight, higher aspect ratio, what's the down side?

Switching to a taller, high aspect ratio board would be one thing. Taking the existing board and making it a foot longer is another.
The TheMightyHobie18 has a very low aspect daggerboard compared to modern designs. If you just make it longer, I suspect the added drag would pretty much cancel out the increased lift- you might point a little higher, but you'll be going slower.

If you could find a pair of modern boards and modified your trunks to use them, then there would probably be a benefit. There was a discussion about doing just that on the Hobie forum not too long ago.

When it comes down to it, you can make lots of fancy changes to the 'ole 18, but in the end, it's still an 18. Enjoy it for what it is.

sm

Lengthening the boards will not help. Its the overall shape that limits the performance. My 18 is also set up like yours and when running against F18s the lift created by their daggers is quite noticeable. My thoughts were to sleeve the existing wells to allow some newer design. My current path is to locate some damaged Tiger boards to create the sleeve. Another option is to buy the dagger well for a tiger and build from the well. Getting the board in the right spot is the most difficult part. The TheMightyHobie18 boards kind of slant back, not straight up and down like newer designs. Finding the proper alignment both left to right and front to rear will not be an easy task and will most likely require some professional guidance. I will be interested in any ideas or attempts to do this! I have some hulls now that are trash and think I may have access to some damaged boards to start to work with.

uhhhh, I don't know what to think after reading this. Is it a sailing question, or some OTHER subject?

Collin,
No offense, your TheMightyHobie18 is definately the nicest one I've ever seen. No matter what, in the end, it will still be a TheMightyHobie18. You gotta decide what you REALLY want that boat to do and how much it will end up costing. You're already pretty close if not past what a good used F18 would cost you. I've sailed around you at the Dike when you were reaching with the wings on it. Your boat speed was about the same as mine for that run. It's a good and fast 18. You may get a couple more degrees going to weather but at what price?
If you give a pig a nose job, you'll still end up with pork chops instead of prime rib.

What you are looking to do is to bring the platform up to the level of the 1980's Hobie 18 Formula 104 by Hobie Cat Europe (pre-tiger). It had high aspect carbon daggerboards and a higher aspect 3 sail rig. Some specs on the SCHRS list. Maybe HC europe can help you out with boards and wells? - if marketing issues don't get in the way.

http://www.youtube.com/watch?v=sR8QSlcpre0

Cheshirecatman

I am actually very happy with how my boat sails. The cost of new daggers from Hobie is more than I what I can have them made for. If I am having them made it would be no big deal to make them a foot or so longer. I was just curious what performance gains or loses there would be. I have to agree with an earlier post that the increased drag would probably out way any increase lift. As for the boat it is what it is. I enjoy tinkering as much as I do sailing. Thats is why I like this platform. It really hasn't been about the money. It has been about the experience. Performance wise the boat is great. In some conditions the F18's and I20 struggle to stay ahead, as proven this last weekend. In other conditions the F18's and I20 wish I would hurry up and finish so that we can get the next race on.