{"product_id":"equal-length-4-1-parallel-merge-collector-headers","title":"Equal Length 4-1 Parallel Merge Collector Headers","description":"The PPE equal length headers are designed to replace factory exhaust manifolds on Lexus RCF, GSF, and IS500 models, offering improved flow and volumetric efficiency through optimized runner lengths and diameters. Each unit features 16-gauge 304 stainless steel tubing that is fully TIG-welded, including 3\/8-inch thick head and outlet flanges, and a 15-degree parallel merge collector for consistent gas pulse expulsion. This design helps balance backpressure at the exhaust ports to aid top-end engine performance.\n\nInstallation requires attention to thermal management, as the manufacturer recommends either ceramic coating or the use of 2-inch wide titanium heat insulation. It is also advised to retain the factory heat shield to protect the starter motor. These headers are intended for racing applications and do not include factory catalysts; consequently, they are not intended for use on public streets or roadways. The package includes new 60mm outlet gaskets and a dipstick relocation bracket.\n\nBecause these headers remove factory emissions equipment, appropriate software calibration or an ECU tune is strongly recommended to support the performance changes. RR Racing, a distributor, offers an optional ECU upgrade tune package alongside this product to maximize power gains.","brand":"PPE","offers":[{"title":"Default Title","offer_id":52663321297208,"sku":"145001-SS","price":2400.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0970\/4895\/3144\/files\/687527827.jpg?v=1784325928","url":"https:\/\/store.motormia.co\/products\/equal-length-4-1-parallel-merge-collector-headers","provider":"MOTORMIA","version":"1.0","type":"link"}