i need dry exhaustwt do you think on these http://www.eddiemarine.com/store/car...l&p=13079&c=63

Those are not dry exhaust. However, the risers are longer than stock mercs, so they should help with reversion. How big of a cam do you plan on running?

Those are the ones I use, only mine are not 3" taller. I have been running 230/235 duration with no problem. My new roller cam witll have 228/234 but more lift. Post your cam specs and maybe some others will chime in.

Those are manifolds.

comp cam 11-414-8 Roller 242IN 254 EX / 566IN 575EX

I would update the post description to Cam advice and see if RMbuilder or one of the other cam experts will chime in. That does not look like a good cam to me. But I am not a engine builder. Most marine cams are much different that that one. Less duration, more lift, LSA of 112 or 114.