I have a CG skytiger, that originally didn't have a cowl, but I made a cowl for it. Goldberg recommends a 2-1/4" spinner, but my cowl's diameter at the front is about 2-1/2". I want to know if using a spinner that isn't the same diameter as my cowl makes it a lot less aerodynamic? I'm using a OS 46fx, can I use a 2-1/2" spinner on it so it's the same diameter as my cowl?

Thanks, Brian