This is a velocity stack, the pic is the mock up after I designed it. I am personally Elegoo PAHT-CF to make it. I am making this for a friend that races Honda automobiles, the engines he uses are the Honda H23 with a throttle body intake of 2 7/8-3 inches. He does run a restrictor plate and this mates up to really well with a silicone boot and clamps on either side to secure it. I am just a hobbyist that is helping a friend and it is something I am learning, I have been learning about 3D printing for just over a year now and am starting to learn how to design things.

, it is a very slow going process as I am at work a lot.