Increasing Intake manifold volume on a 59ci mercury

Good morning everyone,

I recently developed a 3/16" intake manifold spacer for my 59ci mercury in hope of allowing the intake to flow better. I chose to use a thin piece of material (3/16") because i didn't want to increase the volume so much that it hurt the intake charge velocity. I have heard of people running 3 gaskets between the manifold and reed plate to improve performance and that is actually what gave me the idea to make this spacer. I am thinking that this will especially be more beneficial on a high rpm ported power head, rather than on a stock power head. I don't have a dyno or a vbox to really know what the results are and ive also added several other modifications to my power head so its hard to say if it helped or hurt performance. If anyone has any experience with a similar set up on this particular engine or a mid size 2 stroke outboard, please feel free to chime in. I'd love to hear everyone's thoughts on the matter. Would y'all say the increased manifold volume is beneficial or the opposite?Attachment 74632 I have provided an image of the spacer (installed) on my motor. I have a few more that I am willing to sell if anyone is interested in them too.