I am looking for a little help on some 550 upgrades. I have purchased a few parts and looking to put them on my ski, but looking for some advice. I have a '86 550 with a Jetsport Head, aftermarket prop. I purchased a Westcoast pipe and an sbn 44mm carb. I also have another sbn 44mm carb and a kerker pipe for another ski. I want to put these both on and was looking at manifolds for each. Any suggestions? Are Marniner manifolds any good? Do I need an aftermarket manifold for the sbn? Are these worth while upgrades? I have another ski with a stock bn carb and it is a pain in the rear to adjust. Have never been able to get it running right. If anyone has intake or exhaust manifolds for sale please let me know! Thanks.