Surfing Waves

I'd like to talk about fin configurations. I am having my first custom board shaped for me. It's a 7'6 x 23 x 3.1 egg-ish shaped board. The fin set-up is a 4+1, with 4 Futures slots in a quad configuration and a longboard fin box in the middle. With this set-up, I can supposedly ride it as a quad, fiver (quad + "nubster"), thruster (with a small fin in the center box), 2+1 (larger center fin with side bites), or a straight up single. For the basic quad config, my shaper has recommended a particular Futures set that I am going with as my baseline. I'll probably order a little nubster 5th fin just fun. For single fin mode I have a 8.5" Rainbow flex fin that should be fun to try.

My main questions are about the difference between the thruster configuration and the 2+1. For a board this size is there any reason to run a 2+1 config instead of a conventional thruster with 3 equal size fins? What would be the performance characteristic of the larger fin with side-bites compared to the thruster?

Set-up will be something like this:

Best advice would be to experiment. People have different reactions to the exact same fin set up so its hard to say. I have found on boards the size you have that quads work best for me. I have found the 2+1 works the best for me on longboards only and not so much on a 7-6. I once had a 7-6 close to your dimensions with the same fin set up and had to look everywhere to find a center fin to match the side fins I had. I wish I had the board made as a 5 fin with the center fix box being a Future Box. I ended up spending too much money on fins for that board. You might find it to be completely opposite though. Best part is testing though - fins can change everything on how a board rides and fun to experiment. Pray for surf....

I did find some good sources for small (thruster-sized) fins that fit the center box. In case anyone else is looking here's what I have so far:

Thruster trailer fins for longboard slot (2.5, 3.0, 3.5, 4.0, 4.5, 5.0"):
http://www.shop.rainbowfins.com/Thruste ... oductId=93

Small box fin (2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5"):
http://trueames.com/shop/small-box-fin

Small Box fin with 1.5" aft overhang (4.5, 5.0, 5.5"):
http://trueames.com/shop/small-box-fin-with-overhang

Futures small fin for longboard box ("Performance" longboard fin availible in 4.5")
http://www.tactics.com/futures-fins/per ... -fin/clear
http://futuresfins.com/catalog/FUTURES_ ... P_LINE.pdf

Another small, box fin (has thruster side fins in same template) Austrailian:
http://www.cdrivefins.com/mal-center-box-fin-small-4-6/

I love quads for the glide and performance, but I also like 2+1 in mushy big sets.