Precision laser cut from 3/8" thick 304 stainless, our header flanges are manufactured in the U.S. and are machine surfaced. These header flanges were fabricated specifically for the Sonny's BBC 5.3 GM style head. Configured with a 2 1/2" round port for easy header fabrication.
Port Size: 2.505"
We carry over 250 different header flange designs, so if you don't see the flange your looking for, talk with one of our tech reps about custom header flange cutting.
Flanges Sold Separately
