{"product":{"id":11142675333462,"title":"Nostrum GM Gen 5 LT V8 Stage 1 High Flow DI Injectors","body_html":"\u003ch2\u003eSummary\u003c\/h2\u003e\u003cp\u003eStage 1 is Nostrum's first fuelling step for a Gen V LT V8 that runs out of injector before it runs out of blower, turbo or nitrous. They flow 25% more than a stock LT4 injector and 45% more than the LT1 and L86 item, at up to 220 bar, and keep an OEM-equivalent spray pattern so the factory engine management still controls them. Nostrum describes the set as plug and play. Each injector is flow tested and batched into a serialised set, which is what stops one cylinder running leaner than the other seven.\u003c\/p\u003e\u003ch2\u003eBest For\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eA cammed or blown LT1 pegged at injector duty cycle, with no timing or boost left in it.\u003c\/li\u003e\n\u003cli\u003eLT4 cars adding a smaller blower pulley, where the pump still has headroom but the injectors do not.\u003c\/li\u003e\n\u003cli\u003eMoving onto E85 or a high-ethanol blend, which needs roughly a third more fuel volume for the same air.\u003c\/li\u003e\n\u003cli\u003eSilverado, Sierra, Tahoe, Suburban and Escalade builds that tow or tune and want the fuel side sorted first.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eWhere The Stock LT1 And LT4 Injectors Run Out\u003c\/h2\u003e\u003cp\u003eA direct injection fuel system hits two separate walls. In the mid range the cam-driven high pressure pump is the limit; at high rpm the crank angle available for each injection event gets short, and that is an injector problem. Adding boost or ethanol without addressing the injector drives the car further into that second wall. Stage 1 lifts the injector ceiling while leaving the factory calibration structure intact.\u003c\/p\u003e\u003ch2\u003eChecking Your Injector Stem Before You Order\u003c\/h2\u003e\u003cp\u003eLT1 and LT4 style injectors use a 7.5mm stem. The LT2 uses 6mm and will not take this set without machining the cylinder heads, so stem size is the one check to do first. Nostrum flags 2021-onward Silverado, Sierra, Tahoe, Suburban and Escalade in particular: confirm the engine is not already on 6mm stem injectors.\u003c\/p\u003e\u003ch2\u003eKey Specs\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eManufacturer: Nostrum High Performance\u003c\/li\u003e\n\u003cli\u003eProduct type: high flow direct injectors (DI), complete set\u003c\/li\u003e\n\u003cli\u003eSKU: H703-1352\u003c\/li\u003e\n\u003cli\u003eFlow: 25% more than stock LT4, 45% more than stock LT1\/L86\u003c\/li\u003e\n\u003cli\u003eMax operating pressure: 220 bar \/ 22 MPa \/ 3190 psi\u003c\/li\u003e\n\u003cli\u003eInjector stem: 7.5mm, LT1 and LT4 style, not LT2\u003c\/li\u003e\n\u003cli\u003eIncluded: complete injector set, installation instructions, tuning guides for your tuner\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eFitment And Setup Checks\u003c\/h2\u003e\u003cp\u003eA supporting calibration is required; Nostrum recommends HP Tuners or EFI Live and supplies HP Tuners templates. Confirm the 7.5mm stem, then check the car against the table below. The 1200 whp gasoline and 900 whp E85 numbers Nostrum quotes are fuel-system capacity for a build that already has the air handling, mechanical strength and tuning to use it, not an outcome of fitting injectors. If Stage 1 is not enough, the \u003ca href=\"\/products\/nostrum-gen-5-gm-lt-v8-stage-2-injectors\"\u003eStage 2 set\u003c\/a\u003e is the step up; other engines sit in the \u003ca href=\"\/collections\/high-flow-direct-injectors\"\u003ehigh flow direct injector range\u003c\/a\u003e.\u003c\/p\u003e\u003ch3\u003eVehicle Fitment\u003c\/h3\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003e2014-2019\u003c\/td\u003e\n\u003ctd\u003eChevrolet Corvette (C7)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2014-2023\u003c\/td\u003e\n\u003ctd\u003eChevrolet Silverado \/ GMC Sierra\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2014-2023\u003c\/td\u003e\n\u003ctd\u003eChevrolet Tahoe \/ Suburban and Cadillac Escalade\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2016-2022\u003c\/td\u003e\n\u003ctd\u003eChevrolet Camaro SS\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2017-2023\u003c\/td\u003e\n\u003ctd\u003eChevrolet Camaro ZL1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2016-2019\u003c\/td\u003e\n\u003ctd\u003eCadillac CTS-V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003eManufacturer\u003c\/td\u003e\n\u003ctd\u003eNostrum High Performance\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProduct Type\u003c\/td\u003e\n\u003ctd\u003eHigh flow direct injectors (DI)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSKU\u003c\/td\u003e\n\u003ctd\u003eH703-1352\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEngine Application\u003c\/td\u003e\n\u003ctd\u003eGM Gen V LT V8 (LT1 \/ LT4 \/ L86)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFlow Increase\u003c\/td\u003e\n\u003ctd\u003e25% over stock LT4; 45% over stock LT1\/L86\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFlow Rate\u003c\/td\u003e\n\u003ctd\u003e22.1 g\/s at 100 bar (Viscor 16A); 1832 cc\/min at 100 bar (nHeptane)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Operating Pressure\u003c\/td\u003e\n\u003ctd\u003e220 bar \/ 22 MPa \/ 3190 psi\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInjector Stem\u003c\/td\u003e\n\u003ctd\u003e7.5mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFuel Compatibility\u003c\/td\u003e\n\u003ctd\u003eEthanol compatible\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTune Requirement\u003c\/td\u003e\n\u003ctd\u003eYes; HP Tuners or EFI Live\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWarranty\u003c\/td\u003e\n\u003ctd\u003eLimited lifetime (manufacturing defects)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\u003ch3\u003eWill these fit a C8 Corvette?\u003c\/h3\u003e\u003cp\u003eNostrum does not list the C8 for Stage 1. The Stage 2 set covers 2020-2021 C8 cars confirmed not to be on 6mm stems.\u003c\/p\u003e\u003ch3\u003eDo I need port injection or methanol as well?\u003c\/h3\u003e\u003cp\u003eNo. Nostrum's position is that this flow increase removes the need for a secondary port or methanol setup, because the fuel goes through the factory direct injection system.\u003c\/p\u003e\u003ch3\u003eShould I upgrade the high pressure pump at the same time?\u003c\/h3\u003e\u003cp\u003eIt depends where your car is limited. The pump is usually the restriction around peak torque, the injector at peak power. Your tuner's logs will show which wall you meet first.\u003c\/p\u003e","vendor":"Nostrum High Performance","product_type":"High Flow Direct Injectors","created_at":"2026-07-24T13:03:12+01:00","handle":"nostrum-gen-5-gm-lt-v8-stage-1-injectors","updated_at":"2026-09-09T03:06:31+01:00","published_at":"2026-07-24T17:57:55+01:00","template_suffix":null,"published_scope":"global","tags":"brand:nostrum-high-performance, Cadillac, Cadillac CTS-V, Cadillac Escalade, cat:fuel, Chevrolet, Chevrolet Camaro, Chevrolet Camaro SS, Chevrolet Camaro ZL1, Chevrolet Corvette, Chevrolet Corvette C7, Chevrolet Silverado, Chevrolet Suburban, Chevrolet Tahoe, dept:performance-parts, fits:cadillac-escalade, fits:chevrolet-camaro, fits:chevrolet-corvette, fits:chevrolet-silverado, fits:chevrolet-suburban, fits:chevrolet-tahoe, fits:gmc-sierra, GM, GMC, GMC Sierra, make:cadillac, make:chevrolet, make:gm, make:gmc, type:high-flow-direct-injectors","variants":[{"id":54805987787094,"product_id":11142675333462,"title":"Default Title","price":"2295.47","sku":"H703-1352","position":1,"compare_at_price":"","fulfillment_service":"manual","inventory_management":null,"option1":"Default Title","option2":null,"option3":null,"created_at":"2026-07-24T13:03:12+01:00","updated_at":"2026-09-09T03:06:31+01:00","taxable":true,"barcode":null,"grams":0,"image_id":null,"weight":0.0,"weight_unit":"kg","requires_shipping":true,"quantity_rule":{"min":1,"max":null,"increment":1},"price_currency":"GBP","compare_at_price_currency":"","quantity_price_breaks":[]}],"options":[{"id":14231277044054,"product_id":11142675333462,"name":"Title","position":1,"values":["Default Title"]}],"images":[{"id":83087872590166,"product_id":11142675333462,"position":1,"created_at":"2026-07-24T16:01:53+01:00","updated_at":"2026-07-24T16:01:55+01:00","alt":"Nostrum Gen 5 GM LT V8 Stage 1 Injectors","width":500,"height":500,"src":"https:\/\/cdn.shopify.com\/s\/files\/1\/0952\/1849\/9926\/files\/H603-1251-A1_-_LT_DI_Injectors_photo_07__76039.1695303023_91d83e7b-195e-4202-9379-206aa7481516.jpg?v=1784905315","variant_ids":[]}],"image":{"id":83087872590166,"product_id":11142675333462,"position":1,"created_at":"2026-07-24T16:01:53+01:00","updated_at":"2026-07-24T16:01:55+01:00","alt":"Nostrum Gen 5 GM LT V8 Stage 1 Injectors","width":500,"height":500,"src":"https:\/\/cdn.shopify.com\/s\/files\/1\/0952\/1849\/9926\/files\/H603-1251-A1_-_LT_DI_Injectors_photo_07__76039.1695303023_91d83e7b-195e-4202-9379-206aa7481516.jpg?v=1784905315","variant_ids":[]}}}