Can any of you superstars on here help me,I bought a (supposed rs2000)head with a piper mild road cam in it ,the intention was to gas flow it and exchange it with the one already fitted ,since then I have dropped on another head dirt cheap when i compered the 2 the rs head has a distinct curve in the inlet port where as the other is a straight run to the valve ,I assume the straight would be the better for gas flow ,the question is what is the other head off ????and is it any use ,also if it,s not as described I stand a chance of getting my money back thanks in advance gentlemen I,m sure somebody on here knows.