Some of the rock crawler guys have a slightly different setup that accomplishes the same thing as the j tubes without the worry of siphoning fuel out of the bowls. If that's a concern of yours...

There is no USCG requirement for j tube carb vents.

Some of us tend to run like rock crawlers only at a much higher speed. I've been near every angle in and out of the water but not over backwards as of yet and only stuffed one boat. Lol. I like j tubes cause they make it easy to carry your carb. Hah

Even though there isn't a requirement for a j tube, there is a requirement that the carb not be able to leak fuel into the bilge. The Holley style vent system which would normally leak into the bilge accomplishes this by means of the j tube. Anyway that's my .02

Some people are concerned that the airflow by the j tubes will siphon fuel from the bowls even in an upright position. I don't know if this is a valid concern, but if it is the tubes the rock crawlers use prevents it.

Although was a big deal at one time to the CG I've yet to get cked for J tubes in over 30 yrs of boating and been stopped numerous times.

Here is exactly what the CFR reads:
http://i205.photobucket.com/albums/b...psjigjnwbq.png

http://www.uscgboating.org/assets/1/...YC.1002.01.pdf

It's all here. Start around page 40.

I think we get it VC. You've been doing your homework. What do they have to say about nude chicks aboard?

If it's stuck a little heat with a torch will get it moving...LOL.