RB N54/N55 Head Flange with Inserts

These flanges are designed with true tapered inlets and backside stress channels (as they were from the OEM's). They are a 7 piece design (single main 5/16" thick flange, six exhaust runner inserts with locators for 1 1/4” Schedule 10 Weld Els). Unlike competitive products priced comparably and made from cheap material, these are billet machined from 100% 304/304L material (with certs). The proclaimed flange of choice for many educated N54/N55 turbo manufacturers and DIY'ers. Much engineering time, much quality, and much ingenuity is in these flanges all at a great price. Please note we have an identical flange kit but with a twin interface available as well at a slight cost savings.