Custom Billet CNC Header Flanges

We are now offering custom CNC Header and Exhaust Flanges! Precision milled from billet stainless steel, aluminum, or titanium, we can create nearly any custom flange to fit your build's needs.

**We also are constantly adding standard product listings to our CNC flange lineup, with set prices an short lead times.

If you would simply like a CNC profiled version of our existing header flange line up, simply give us the product number and port size you're looking for.
(Example: Big Block Chevy Round Port Flanges, #SHM-1490-SHF, 2 1/2" port size)

 Option Descriptions

• Material Type
  
  • 304 Stainless Steel: Great universal performance, the standard material for performance automotive headers of all types
  • 316 Stainless Steel: Improved corrosion resistance from 304 stainless. Great for Marine use. No added benefit in boosted/nitrous applications
  • 6061 Aluminum: Not for use as a header flange. Only recommend using for flange adapter plates, or header/manifold spacers.
  • CP2 Titanium: Extremely durable, lightweight, and strong. Requires use of full titanium headers or exhaust. Cannot be welded to other metals. Highly encouraged for those chasing significant weight savings who aren't on a budget.
• Engine/Cylinder Head Description
  
  • Simply let us know what your engine & head combination is. We will use this information to send you a draft of the flange design, and await your approval. You may also simply add an existing SHM part number to this field and we will generate a CNC version of our existing Laser Cut Header Flanges
    
    
• Flange Thickness
  
  • We offer all of these flanges in 3/8" or 1/2". Other options are available as special request.
  • 3/8" is standard for nearly every application. These work great for boosted, nitrous, N/A headers, as well as header repairs
  • 1/2" is great when additional strength is needed to support turbochargers
  • 1" is for aluminum header/manifold spacers or adapters only. We will not offer 1" thickness for our stainless or titanium flange options
• Lightened Flange
  
  • We will further remove material from the base design, either by adding in holes to the design, or creating pockets in the flange to remove further weight. Not compatible with all designs or flange applications.
    
    
• O-Ring Groove
  
  • An added bonus for those wishing to eliminate the use of header gaskets. We will confirm the location and size of the o-rings being used, and add a custom o-ring groove on the mating surface of your flanges. O-Rings will be included in your package to verify fitment and correct installation.
    
    
• Counterbore
  • For this, we add a 'step' to the header side of the flange, limiting your tube insertion to only 80% of the depth into the flange. This is beneficial when wishing to add oversized tubes to an otherwise limited port shape. For improved strength, we do not recommend adding the counterbore, as the headers will be stronger when the tube is fully inserted through the flange.

The list price is for reference only, it is NOT the final price on the flanges. You will be given a final quote to confirm based on your design choices before the order is approved and put into queue.

Whether you are looking for custom port alignment, new contours and flanges peripherals, contoured and molded exhaust ports, or even ultra-lightweight options, we can supply it.

Every flange will be precision skimmed to ensure flatness and straightness. All bolt holes and flange port holes will be precisely chamfered for a smooth, bur free edge.

These custom CNC flanges will be offered in 3/8" and 1/2" thickness, great for conventional headers, supercharged engines, nitrous builds, turbo headers, or zoomie header applications.