{"product_id":"upper-intake-manifold-with-gasket-for-chevrolet-lumina-1998-1999-3-8l","title":"Upper Intake Manifold with Gasket for Chevrolet Lumina (1998-1999) 3.8L","description":"\u003ch2 style=\"font-size: clamp(18px, 3vw, 21px); margin-bottom: 15px; line-height: 1.3;\"\u003eDirect-Fit Upper Intake Manifold with Gasket for 1998-1999 Chevrolet Lumina (W-Body)\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat it Does:\u003c\/strong\u003e The Upper Intake Manifold with Gasket replaces the failure-prone factory plenum on the 1998-1999 Chevrolet Lumina to stop unmetered vacuum leaks and prevent catastrophic internal coolant ingestion into the cylinders.\u003c\/p\u003e\n\n\u003ch3\u003eThe Stock Chevrolet Lumina Intake Plenum Degradation\u003c\/h3\u003e\n\u003cp\u003eThe factory upper intake on the \u003cstrong\u003eW-body\u003c\/strong\u003e Lumina equipped with the \u003cstrong\u003e3800 Series II L36\u003c\/strong\u003e V6 is notorious for catastrophic structural degradation. The OEM composite nylon plenum directly interfaces with a high-temperature exhaust gas recirculation (EGR) stovepipe. Continuous thermal cycling and localized exhaust heat cook the thin polymer wall adjacent to the coolant bypass passages. Over time, the plastic softens, cracks, and erodes, introducing pressurized coolant directly into the intake tract. This thermal degradation triggers severe misfires, unmetered air intrusion, catalytic converter fouling, and catastrophic engine hydrolock if left unaddressed.\u003c\/p\u003e\n\n\u003ch3\u003eThe Engineering Solution\u003c\/h3\u003e\n\u003cp\u003eThis replacement upper intake plenum is molded from high-grade, heat-stabilized composite polymer engineered to resist prolonged thermal fatigue and chemical breakdown from fuel vapors and engine coolant. The critical runner walls and EGR interface zones feature reinforced material thickness to prevent heat sink erosion. Paired with a precision-molded port gasket utilizing vulcanized elastomeric sealing beads, this manifold creates a hermetic air-fuel seal across the lower intake base. It restores correct manifold absolute pressure (MAP) readings, stabilizes idle vacuum, and prevents coolant crossover leaks under high thermal stress.\u003c\/p\u003e\n\n\u003ch3\u003eWhat's Included\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e1 Upper Intake Manifold (plastic)\u003c\/li\u003e\n  \u003cli\u003e1 Upper Intake Manifold Gasket with port seals\u003c\/li\u003e\n  \u003cli\u003eFuel pressure regulator spring\u003c\/li\u003e\n  \u003cli\u003eThrottle body studs\u003c\/li\u003e\n  \u003cli\u003eO-rings and fittings as pictured\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cdiv style=\"overflow-x: auto; margin-bottom: 20px;\"\u003e\n  \u003ctable width=\"100% style=\" border-collapse: collapse border: solid font-size: min-width:\u003e\n    \u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eFitment\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e1998-1999 Chevrolet Lumina\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eEngine \/ Chassis\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e3.8L V6 (L36 \/ 3800 Series II) \/ W-Body\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr style=\"background-color: #f9f9f9;\"\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eStock Output\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e200 hp \/ 225 lb-ft\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003cth style=\"padding:10px; text-align: left; border: 1px solid #e0e0e0;\"\u003eReplaces OEM Part #\u003c\/th\u003e\n\u003ctd style=\"padding:10px; border: 1px solid #e0e0e0;\"\u003e106001, 217454, 871601, 12537425, 24506013, 89017272, 89017274, CE1413044, FH10095, SK615180, XTA016, 615180, 11396399\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e1998 Chevrolet Lumina 3.8L V6 Gas Naturally Aspirated\u003c\/li\u003e\n  \u003cli\u003e1999 Chevrolet Lumina 3.8L V6 Gas Naturally Aspirated\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eFrequently Asked Questions \u0026amp; Fitment Warnings\u003c\/h3\u003e\n\u003ch4\u003eDoes this fit the W-Body Lumina?\u003c\/h4\u003e\n\u003cp\u003eYes, this is a direct fit for the 1998-1999 Chevrolet Lumina equipped with the \u003cstrong\u003e3800 Series II (L36)\u003c\/strong\u003e 3.8L engine. \u003cstrong\u003eThis kit does not fit 3.1L V6 models.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003ch4\u003eWhat critical steps should be followed during installation?\u003c\/h4\u003e\n\u003cp\u003eFasteners must be torqued in the factory-specified sequence on a completely cool engine to ensure even gasket compression and prevent manifold ear fracture.\u003c\/p\u003e\n\n\u003ch3\u003eThe Chevrolet Reliability Standard\u003c\/h3\u003e\n\u003cp\u003eEngineered to restore original powertrain integrity, this intake manifold assembly eliminates the primary Achilles heel of GM's legendary 3800 powerplant, ensuring sustained fuel metering accuracy and long-term operating durability.\u003c\/p\u003e","brand":"VelocityMax","offers":[{"title":"Default Title","offer_id":68038526828792,"sku":"DS-EI9L279G7","price":99.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/1290\/2648\/files\/upper-intake-manifold-with-gasket-for-chevrolet-lumina-1998-1999-3-8l-1.jpg?v=1794200988","url":"https:\/\/performancechiptuning.com\/fr\/products\/upper-intake-manifold-with-gasket-for-chevrolet-lumina-1998-1999-3-8l","provider":"Performance Chip Tuning","version":"1.0","type":"link"}