{"product_id":"mangum-racing-235cc-cnc-ported-cathedral-cylinder-heads-pair-assembled-6-bolt","title":"Mangum Racing 235cc CNC Ported Cathedral Cylinder Heads PAIR - Assembled - 6 Bolt","description":"\u003cp\u003e\u003cstrong\u003eMangum Racing 235cc CNC Ported Cathedral Cylinder Heads PAIR - Assembled - 6 Bolt\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cdiv\u003e\n\u003cp\u003eMangum Racing CNC Ported MR 15° LS Cathedral Port Cylinder Heads\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003eBuilt from your choice of 4-bolt or 6-bolt 15° LS casting featuring increased deck thickness, the MR 15° LS1 is engineered for serious naturally aspirated and boosted combinations that demand airflow, strength, and repeatability, while maintaining OEM valve angle and valve location geometry.\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003eFeaturing a 2.065\/1.60 valve combo the 235cc version easily clears the bores on 5.7L engines and up!  This is not a simple LS6 cylinder head copy, this is a ground up designed cylinder head with fully cnc ported ports \u0026amp; chambers for optimum power \u0026amp; performance.\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003eThis casting is designed to support 1,500+ horsepower combinations when paired with the proper short block and induction system, making it an ideal solution for builders who need maximum performance without moving away from stock valve layout.\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003eEach set is fully CNC ported in-house on new Centroid 5-axis machining centers and finished on Newen seat and guide equipment. Every cylinder head is hand blended, inspected, and assembled in small batches to ensure dimensional accuracy and consistency.\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eAirflow Performance\u003c\/strong\u003e\u003cbr\u003eTested on a SuperFlow bench\u003c\/p\u003e\n\u003cp\u003eIntake (Radius Entry):\u003c\/p\u003e\n\u003cp\u003e.200” – 138 CFM\u003cbr\u003e.300” – 207 CFM\u003cbr\u003e.400” – 262 CFM\u003cbr\u003e.500” – 295 CFM\u003cbr\u003e.600” – 322 CFM\u003cbr\u003e.700” – 330 CFM\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003eExhaust (No Pipe):\u003c\/p\u003e\n\u003cp\u003e.200” – 107 CFM\u003cbr\u003e.300” – 152 CFM\u003cbr\u003e.400” – 198 CFM\u003cbr\u003e.500” – 226 CFM\u003cbr\u003e.600” – 239 CFM\u003cbr\u003e.700” – 244 CFM\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003eWith a 235cc CNC intake runner and optimized 99cc exhaust port, the MR 15° delivers strong mid-lift efficiency and stable high-lift airflow, ideal for 3.900\" and larger bore engines)\u003c\/p\u003e\n\u003cp\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePremium Hardware \u0026amp; Construction:\u003c\/strong\u003e\u003cbr\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e6-bolt Mangum Racing LS1 casting with increased deck thickness\u003c\/li\u003e\n\u003cli\u003e15° valve angle with OEM LS valve spacing\u003c\/li\u003e\n\u003cli\u003e6 Bolt Casting\u003c\/li\u003e\n\u003cli\u003e2.065” stainless intake valves\u003c\/li\u003e\n\u003cli\u003e1.60\"  stainless exhaust valves\u003c\/li\u003e\n\u003cli\u003eBronze guides\u003c\/li\u003e\n\u003cli\u003ePAC dual spring package\u003c\/li\u003e\n\u003cli\u003eTitanium retainers\u003c\/li\u003e\n\u003cli\u003eViton seals\u003c\/li\u003e\n\u003cli\u003e1.250” steel spring seats\u003c\/li\u003e\n\u003cli\u003e63.5cc CNC chambers (milling available at no charge)\u003c\/li\u003e\n\u003cli\u003eChamber softening options available\u003c\/li\u003e\n\u003cli\u003eFlat milling at .007” per cc\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMinimum bore: 3.900” (LS1\/LS2\/6.0L)   \u003c\/strong\u003e  \u003cspan style=\"color: rgb(255, 42, 0);\"\u003e\u003cstrong\u003e4.8L\/5.3L Must Use 229cc Design\u003c\/strong\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003e4.060\" minimum gasket bore\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003eBuilt for High-Output Stock-Geometry Combinations\u003cbr\u003eThe increased deck thickness provides added durability under elevated cylinder pressure, while the 15° valve angle maintains compatibility with stock-style piston valve reliefs and factory-based valvetrain geometry.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003eThe PAC dual spring system offers the stability required for serious street or race camshaft profiles, and stock pushrod length works in many applications (final length should always be verified based on camshaft and milling).\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003eFor builders who need to retain OEM valve angles and locations but demand serious airflow capability on a smaller bore LS engine, the MR 15° LS1 235cc casting delivers.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Mangum Racing","offers":[{"title":"Default Title","offer_id":48431677472966,"sku":"Mangum235","price":2099.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/2716\/4086\/files\/mangum-racing-mangum-racing-235cc-cnc-ported-cathedral-cylinder-heads-pair-assembled-6-bolt-1264875317.png?v=1793081768","url":"https:\/\/www.glennsautoperformance.com\/products\/mangum-racing-235cc-cnc-ported-cathedral-cylinder-heads-pair-assembled-6-bolt","provider":"Glenn's Auto Performance","version":"1.0","type":"link"}