Then Change to 4-2-1: (Stainless Steel, No more clearance issue) (Power starts at 1.5k~2k RPM)
After 2 Days: (Stainless Steel change color to Yellowish after Heated by Exhaust Gas)
Overall comment is 4-1 is very good for track and Drag as it power at top range is still better than 4-2-1. It does suffer in town driving due to need to maintain 3k RPM and Low clearance.
The 4-2-1 is more suited for town driving as the power starts at 1.5k~2k RPM and it does not suffer low clearance issue. The drive is smoother but less powerful on the TOP End RPM if compared to 4-1.
Yellowish mark can be used as a tell tale sign that a Stainless Steel header has been used before.
