{"product_id":"m311-ls3-cylinder-heads","title":"M311 LS3 Cylinder Heads","description":"The Frankenstein M311 273cc LS3 Cylinder Heads represent a substantial upgrade over OEM heads, engineered to deliver horsepower far beyond stock capabilities. Each head is fully CNC ported with a 5-axis high-performance program, then meticulously hand-blended and deburred to ensure extreme attention to detail and precise tolerances, backed by strict quality control processes.\n\nThese \"Monster Series\" heads feature a 68cc chamber volume, a 273cc intake port, a 112cc exhaust port, and an 11° valve angle. The exhaust ports are O-Ringed with hi-temp silicone o-rings included, and 2\" headers are recommended for optimal performance.\n\nBuilt to order, these cylinder heads have an approximate lead time of 4-6 weeks for completion. Both the standard \"Monster\" and the \"Boost Monster\" versions are designed to fit all standard equipment, including valve covers, headers, LS3 intakes, and OEM-type LS3 rocker arms, though billet rocker stands are available separately.","brand":"Frankenstein","offers":[{"title":"Default Title","offer_id":52688449012024,"sku":"113005-LS3","price":3600.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0970\/4895\/3144\/files\/663175903.webp?v=1784890199","url":"https:\/\/store.motormia.co\/products\/m311-ls3-cylinder-heads","provider":"MOTORMIA","version":"1.0","type":"link"}