If your using the factory cradles on your trailer and the boat is adequately strapped down so that it won't "hop" on the trailer. The foam is not necessary. In fact if the boat is on the trailer right in the factory cradles the boat is either not on the trailer right or its putting too much pressure on the hulls. (ie I squish-a- your hull). If the boat is on the trailer right the only shock that is on the boat is on the mast/mastcradle -- cross beam point. Look at how much the mast wiggles as you cross a railroad track. Thats where you need foam -- not hull to trailer. You can put shocks on a trailer -- use go-cart shocks and a welder to weld on shock mounts to the trailer body and then to the axle. Make them angle in towards the center of the axle one in front one in back. It works great and alot of the 4wheel guys are modifiying their old jeep suspension into this configuration due to extra flex off road and a smoother road ride.



Hope that helps.

Steve