Header Flanges

These header flanges come in mild steel or stainless steel. The flange exhaust ports are 38.1mm/1.5" so you can use either mild steel or stainless steel 1.5" tubes. The 8 mounting positions have been cut to 10mm. The holes will be slightly tapered so they will be about 9.8 or 9.9 on one side. This is due to the nature of water jet cutting.

The size has been left this way so that you can use maybe a 10.2 drill to create a nice snug fit to your own head studs. Other manufacturers may cut bigger holes to start with, but this way is better as it allows for much greater accuracy for port matching. If you had a sloppy fit the headers will not go back into exactly the same position each time it is removed from your engine.

With a snug fit it will match up perfectly every time. These flanges were designed by an enthusiast for fellow enthusiasts. They were designed using AutoCAD and are water jet cut with a high precision CNC machine.