I was wondering what are the advantage of stepped headers as oposed to regular headers. do they hurt performance. would you ever run them on a small block.

Stepped headers offer no benefit at all in a street/strip application. There is some benefit in an all-out race engine, but only at high rpm. The engine will need to have a lot of duration and overlap to benefit from stepped header design and even then the header is only "in tune" over a very limited RPM range.

We used them on a mild circle track car I used to work on with pretty good results. I think the basic theroy is sound, to keep the exhaust velocity up and help scavenging. As with anything else, they must be part of the combination or they may hurt more than help. I will be calling Shoenfeld when it comes time for headers for my car.

Jeff