D. Marine Shotgun Silencers
 

I was wondering how far the butterfly should open at full throttle. I put the motor at 5000 and they seemed to only be open about 1/2 the way...So are they supposed to open horizontal (100%)???I have the Shotgun III's they do not have the holes in the butterfly just under the belly of the silencer.. I read the directions and they only explain about adjusting the opening rate not amount....

"Bad-Habit"

I'm running about 450 hp thru mine and they do not open all the way either. About half way. Griff is running a Merc. 525 SC and his do not open all the way either. Drew told me that they almost never do unless you're running HUGE hp thru them. But I have tied them 100% open and did NOT gain a single rpm versus the way they open on their own. So I'm not worried about it at all.