BD focused on solving one of the Ford 6.7L common failures, the exhaust manifolds. Crafted with a heavy duty 0.275 in. thick - walled Hi - Silicon ductile casting, this makes these manifolds 75 thicker to combat cracking due to high exhaust temperatures. Thermal durability has been improved with longer exhaust studs and spacers plus thicker, more durable machined bolting flanges. Fully EGR compatible, BDs exhaust manifold set is the perfect replacement for reliability and peace of mind.