Getting an air tight seal between the intercooler and intake horns can be a tricky task with getting the snoot boots to seat correctly. A handy tip is using silicone bands stretched over the intake and exit allowing the snoot boots a more pliable surface to seal to.

MaCh.P Designs Offer these in their online shop: https://www.machpdesigns.com/product-page/intercooler-silicone-sealing-bands