If I start replacing components on my 5.5sl with ones made of carbon, what will the impact be on the rules (assuming I maintain min weight....

-Carbon mast... not nessicarily from performance, as I can get one from AU for less than half PC cost
-Carbon beams
-Carbon crossbar, tiller-extension, over-rotator, etc..

What can I replace, what can I not??

TheoA,

Print yourself a copy of the Nacra Class Rules.

http://members.tripod.com/UNI55/inca.htm

You can't modify much without being out of the class rules.

I couldn't sail in the recent Performance Nationals that took place in my backyard, because my Nacra 6.0, brand new sails were not made by Skip Elliot nor purchased from Performance.

But, that's another story........

I should have clarified my position.

I don't care about racing in class, as I've never come across a class of 5.5sl's.

What I do care about is taking a hit in PN. If I get a carbon mast exactly like a 5.5uni, but it isn't made by performance and offers no advantage other than price, does that lower my PN ?

Some points that I picked up.

I can't do crap to the boat unless I pay performance or a dealer for their overpriced parts (most).
It says that spin is OK for distance, doesn't specify the chute size, but it specifies a pole length. ?????
When I look at DPN, it doesn't say anything about pole length, or chute size, only that a spin on that boat will drop the # by XX points.

The mast is what I'm really interested about.

The Uni mast is taller than the Sloop mast. That will cause a new and probably larger mainsail. I always thought the Uni mast and mailsail with a sloop jib would be a pretty high horsepower boat. I would be concerned about the stock jib having the same relationship to it's running rigging and blocks. I think the hounds on the Uni are higher than on the sloop.

I don't know if the carbon is accounted for in Portsmouth, but I do know that the carbon mast makes the Uni faster than it was with aluminum. The Michigan Uni fleet found that it was necessary to have the carbon mast to remain competitive. Portsmouth should have a correction for it, even if it doesn't. You might contact Darline Hobock and ask for a provisional number.

Strictly speaking, a carbon mast on a 5.5 sloop means you're not sailing class legal configuration, so the RC can penalize you anyway they feel is fair.
If you want get a Portsmouth number, what I would recommend is to rig it that way, race a few races with the understanding you are not racing for a trophy, only racing generate times for Darlene so she can generate a provisional number. Make sure the RC & regatta chair know what you are doing, announces it to the other competitors, and submits the data to Darlene.
An alternative is to buy a 5,5 uni carbon mast, and race it as a uni.

one correction is the current Nacra rules are located at Nacra Class I saw a modified 5.5 sailing on a Lake in Madison, Wi. Motored over to the owner, boat was a 5.5uni with carbon mast, special light rudders, & large jib ( I think it was a new 5.8na jib)boat was modified by the Nacra dealer.
There's a post on the old forum by Carl, he talks about another Modified 6.0 called the Cathouse 6.0/20
fair winds
Ted

I researched this some and basically it depends on who you race and the race committee. When there is not an accepted modification to PN for a given modification then the RC can make one up. Or if the guys you race with don’t care then they leave it alone. I would make it an A boat and make it as light as you can. (You can look up their rules. good "class" to be creative in). The bottom line is that PN #'s are averages of like boats and unless there is a bunch of people with the same mod it never gets an accepted number so the RC makes it up. And as you can tell you can not do anything except replace a part and be "class legal"
my $.02