Pro Series Header Build Kits: Big Block Chevy 481x

This header build kit has everything you need to bring that Chevy custom header together. Designed to fit the aftermarket Alan Johnson Performance Engineering 481x cylinder heads. Great for building that set of headers for any high performance application. See why Stainless Headers Mfg., Inc has the most complete header builder kit on the market for building your own custom headers. (HP recommendations at the bottom of this page) What makes our header build kits the choice of top fabricators?

Included are:

• Flanges: 2 American made precision laser cut 3/8� thick header flanges to fit the Big Block Chevy Square port heads.
• Port Size: 2.13" or 2.50"
  
• Mandrel Bends: We supply (12) 180 degree J bends. Our J bends come with a 6� & a 12� leg. For most header builds, this extra leg length mean you won�t need to buy any straight tubing. What makes our stainless mandrel bends truly a unique product? We start off with an American made 304 stainless raw material, that is then bent in the U.S. for a genuine 304 .065 stainless bend. Our material forms better, welds better and last because it is a genuine 304 stainless.
• 4 into 1 Collectors: From there we supply a precision formed 4 into 1 collector or a set of our optional super high flow slip on merge collectors with 4 sets of collector tabs. Just like our stainless bends, we start off with an American made 304 stainless and fabricate the industries finest collectors . We offer these header kits with 3 different collector options:
• Formed weld on collectors (Collector stars included)
• Slip on merge collectors with a straight exit (Collector tabs included)
• Slip on merge collectors with a transitional exit (Collector tabs included)
• Collector stars: A simple part that really helps speed up the fab process. Used as a weld in block off between the 4 tubes before welding the collector on, these are precision laser cut for a perfect fit between your specific primary tubes.
• Purge Caps: This simple, but effective method for back purging caps works great. Each kit includes 4 primary caps and one collector cap.
• O2 bungs: Each header builder kit includes 2 weld on O2 bungs. Precision machined in the U.S. from 304 stainless billet, these bungs weld beautifully, not like a cast bung
• Tig Filler Rod: Includes � lbs. package of filler rod:

Because of the wide variety of engine chassis configurations these HP numbers are for general reference only

2 1/8" Primary Tube Header Kit: 650-900 Naturally Aspirated Horsepower

2 3/8" Primary Tube Header Kit: 1000-1200 Naturally Aspirated Horespower

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