We did some testing this weekend with pipe and header combinations on our CRE Plus-4. I ran the 41001 header with the 9886 pipe. The motor seemed to respond very well to the pipe and header change. The 41001 provides good power and a smooth acceleration, and the 9886 provides great power and good fuel economy. The CRE Plus-4 really liked this setup, and this is the best combination that I have found to run on the motor. The 9901ss pipe also runs well, provides a little more bottom end to the setup. Both pipes run great on the 41001 header, just personal preference on which one you like more. Just figured id share some of the information ive gained through testing with the CRE crew. Thanks Neal for all the help, motors are still running great as usual.