figured this might be a good one to post up for anyone not wanting to drop $400+ on FAE. i made this last year and after a little tweaking it worked like a charm for 100+ hours. i went from having VERY visible exhaust fumes hitting my riders to zero visible fumes and a much quieter exhaust. quieter exhaust=better sound system i had an issue the summer before where after surfing i got a really bad headache, then when surfing the next day and having zero symptoms beforehand, got the same splitting headache as soon as i started riding. it's worth the effort to put those fumes into the water so it doesn't affect your surfers.
this build took some trial and error because it fell off the first couple times out. the rubber hose to the stock plastic outlet is hose clamped, and the abs elbows and such have pvc cement holding them together. this is the same hose that is used on exhaust manifolds. there was still some twisting of the downpipe (outward) after a couple rides so i added two stainless screws to each elbow on the exit side to keep that from happening. the original downpipe came out after a couple weeks, so i replaced it and added two stainless screws where the downpipe mates to the 2:1 exit elbow and haven't had a problem since. in addition to that and not pictured is some galvanized wire that i wrapped around the pipe on each side and then around the fixed wake plate adjusters to make sure it wouldn't come off. no issues since doing that. also not pictured is that once i replaced that downpipe, i angled the exit much like the traditional FAE.
hope this helps someone!