It's taking me almost an entire year...and we have finally completed building a one piece equal length jet coated header for a 944 S. I don't have final dyno figures yet(It's going on the dyno Monday), but just putting the mock up set on the car made a significant difference. You can purchase them from MSDS. Ask for Marty....here's the web site...http://www.msdsinc.com/exhaust_1.htm