Already proven on my 32 active thunder to pick up 3-5 mph as others have done it, also they dont do much for you unless your over 80mph. Ill let you all no my gaines in a couple months.

Is it ok to just put a few tack welds on the cone to the case with out gutting the case before epoxying to help from epoxy cracking from flex. Wasent sure of the heat hurting anything.

so if you have cones on a bravo one twins that runs 65 mph that boat may be a little faster without them? i didnt install them so i didnt get to see the difference...

yes it could be faster with out, depends on the hull the x demension. Try a set of stock ones see what you get.