yeah all k series motor’s are simialar mine just has the better head design like the rsx-s and the tsx motor’s. cam’s would work but not give much power increase, header would but it wouldn’t end up bolting up to my exhaust then
when you went to test drive an si are you sure the seat was the entire way down they have height adjustable seats im about 5-10 and i keep it the entire way down and still have atleast 4-5 inches of room about my head