The original poster used the handle HDDP, I thought it was you................
Sorry for the confusion, as I mentioned I thought the poster was you asking the question.
The response was from a guy (Linh Nguyen) that put a header on an SLK 230, he didn't read, or didn't know that your Crossfire had the V-6. The 4 banger apparently showed no gains from the header on a dyno. The reason being that the stock header was designed pretty decently.