I just ordered a set of schumacker shorties. I was told these are easy to install and have plenty of clearence for plugs and the started. I am putting them on a 71 challenger with a 440. I am taking of a set of super competion hookers. The passenger side is to low. I was told with the shorties they won't hang down under the car. I have lowered mine a little with 17 rims and 40/ 245 tires. So the headers were dragging on speed bumps. As soon as I get them and get them mounted I will let you know how they worked out.