{"product_id":"supertech-bmw-toyota-b58-sodium-filled-exhaust-valve-inc-m340i-540i-z4-m40i-a90-gr-supra","title":"B58 engine sodium-filled exhaust valve TEVI-1058-HS for M340i, 540i, Z4 M40i, GR Supra A90","description":"\u003cp\u003eSupertech TEVI-1058-HS is a genuine sodium-filled exhaust valve built for B58 engines in the M340i, 540i, Z4 M40i and GR Supra A90. Designed for fast-road or track-day use where stock valves struggle with heat.\u003c\/p\u003e\u003cp\u003eFeatures an Inconel\/Nimonic head and hollow sodium-filled stem for superior thermal management. Not a generic 'OEM replacement' - it’s a functional upgrade for stage 2 and beyond.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eStem diameter: 0.234 in | Overall length: 3.940 in | Head diameter: 1.122 in\u003c\/li\u003e\n\u003cli\u003eSingle valve - requires Supertech 6 mm single valve lock conversion and intake integral stem seal for full fitment\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Supertech","offers":[{"title":"Default Title","offer_id":54913736081751,"sku":null,"price":80.14,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1038\/4575\/7271\/files\/SupertechBMWToyotaB58SodiumFilledExhaustValve_Inc.M340i_540i_Z4M40i_A90GRSupra_-1_1946x_64d8a13b-b6e4-4c6c-8c0f-d78b361b4b78.jpg?v=1788714907","url":"https:\/\/cuzracecars.com\/products\/supertech-bmw-toyota-b58-sodium-filled-exhaust-valve-inc-m340i-540i-z4-m40i-a90-gr-supra","provider":"Cuz Race Cars","version":"1.0","type":"link"}