Got a chance to test my header on a customers 2 door 2006 Civic SI.
BIG THANKS TO MAINSTREAM PERFORMANCE, for allowing me to use their Dyno again. They did the install as well.
Installed Clearance pics
Exhaust after install
GROUND CLEARANCE
Dyno test was performed back to back on the same day within 2 hours of each other.
NO TUNING PERFORMED. CAR is 100% BONE STOCK, Stock Intake Box, Stock Exhaust, stock ECU.
I simply unbolted the stock header and bolted mine on. 3 pulls on each, best from each runs selected
Solid 13-14whp Gain. Enjoy