{"product_id":"je-pistons-sub-sti-ej257-99-75mm-bore-cr-8-5-kit-set-of-4-pistons-296348","title":"JE Pistons SUB STI EJ257 99.75mm Bore CR 8.5 KIT Set of 4 Pistons - 296348","description":"\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003e\u003cstrong\u003eJE Pistons Forged Piston Set — Subaru EJ257 99.75mm, 8.5:1 (296348)\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003eAn 8.5:1 dished set at +0.25mm over, and the compression ratio is the whole story. This is a piston for a big-turbo, high-boost EJ257 — lower than the 9.8:1 sets most builds run, which trades some off-boost response for real detonation margin once you're pushing serious pressure or chasing a big power number on E85.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003eJE forges from 2618 aluminum, the alloy that handles the heat and cylinder pressure a boosted flat-four generates without cracking a ring land. Their perfect skirt profiles and precision machining keep the piston stable in the bore and the ring package sealing under load.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003e\u003cstrong\u003eFitment:\u003c\/strong\u003e Subaru EJ257 — 04+ WRX STI, 06-14 WRX. 99.75mm bore.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003e\u003cstrong\u003eThe right call if\u003c\/strong\u003e you're building past what a 9.8:1 piston is comfortable with: a big single turbo, high boost on ethanol, or a car that spends its life at wide-open throttle. If the build is a street car on pump gas at moderate boost, the higher compression set will feel better everywhere.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003e\u003cstrong\u003eTwo things to plan for.\u003c\/strong\u003e +0.25mm means the block needs boring and honing. And 2618 grows with heat — set piston-to-wall clearance to JE's spec for your boost level, not to a generic number, or you'll scuff a skirt on the first cold start.\u003c\/p\u003e\n\u003cp class=\"font-claude-response-body break-words whitespace-normal\" dir=\"ltr\"\u003eSet of 4 pistons with rings, wrist pins, and locks.\u003c\/p\u003e","brand":"Street Strip Supply","offers":[{"title":"Default Title","offer_id":47228761079981,"sku":null,"price":872.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0779\/8105\/7197\/files\/296348.jpg?v=1786814058","url":"https:\/\/streetstripsupply.com\/products\/je-pistons-sub-sti-ej257-99-75mm-bore-cr-8-5-kit-set-of-4-pistons-296348","provider":"Street Strip Supply","version":"1.0","type":"link"}