Fuel Injector Clinic 1000cc Injector Set LS3 / LS7

SKU: is303-1000h
Price
$924.00
Currently Backordered - You can still place your order and we'll ship your order as soon as the product is back in stock!

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Installation Services

Don’t worry about the hassle — let our expert team at Forza Motorworks handle the installation for you. Our professional installation ensures everything fits and operates exactly as intended, giving you clean, factory-quality results, proper wiring or mounting, and avoiding the risks of DIY mistakes. You’ll save time, avoid frustration, and get peace of mind knowing the job is done right the first time. Contact us to learn about our installation services and enjoy a seamless upgrade from day one.

FAQ

Shipping Information
For items that are in stock, purchases made after 9am EST will be usually be shipped out in the next 1-2 business days. Please inquire to confirm lead times if you have specific time constraints. Orders will be sent via signature required at our discretion unless otherwise requested. 

International Shipping
Any and all customs duties, taxes, import fees, and/or tariffs assessed in connection with the purchase shall be the sole responsibility of the customer/end user.

Cancellations / Returns

Original sales receipt or order number must accompany all return requests.

Forza Motor Works accepts returns for exchange, store credit, or refund within fourteen (14) calendar days of the delivery date, subject to the terms and conditions below. After fourteen (14) calendar days, all sales are final unless otherwise approved in writing by Forza Motor Works.

To be eligible for return, products must be in new, unused, unaltered, and resalable condition, including all original packaging, instructions, hardware, documentation, and accessories. Returned items must not show any signs of installation, use, wear, damage, modification, painting, coating, or alteration of any kind.

The following items are non-returnable and non-refundable:

• Special-order products
• Custom-built or made-to-order products
• Products manufactured to customer specifications
• Custom color or finish products
• Manufacturer-direct-shipped products designated as non-returnable
• Products with extended lead times, including but not limited to headers, exhaust systems, wheels, and other special-order performance products
• Any item specifically identified on the product page as non-returnable

Orders for special-order, custom-built, made-to-order, vehicle-specific, or manufacturer-direct-shipped products may not be canceled once the order has been submitted to the manufacturer.

If an item is received damaged during shipping or was shipped incorrectly by Forza Motor Works, Customer Support must be contacted within forty-eight (48) hours of delivery. Claims for shipping damage must include clear photographs of the product, packaging, shipping box, and shipping label at the time of unpacking.

Products determined by Forza Motor Works to have been incorrectly shipped may qualify for replacement, store credit, or refund at our sole discretion. Manufacturer defects are subject to the applicable manufacturer's warranty policies and procedures. Forza Motor Works does not provide any separate product warranty unless expressly stated in writing.

All returns must be authorized prior to shipment and must be assigned a Return Merchandise Authorization (RMA) number. The RMA number must be clearly displayed on the outside of the return package. Returns received without an authorized RMA number may be refused or denied credit.

To obtain a Return Merchandise Authorization (RMA), please contact:

Forza Motor Works
Email: info@forzamotorworks.com

All refunds, exchanges, and store credits are contingent upon inspection and approval of the returned merchandise. Forza Motor Works reserves the right to deny any return that does not comply with this policy.

Approved returns may be subject to a restocking fee of up to twenty five percent (25%) of the purchase price. Original shipping charges are non-refundable. Customer is responsible for all return shipping costs unless the return is the direct result of an error made by Forza Motor Works.

FITMENT, INSTALLATION & PRODUCT USE

Customer is responsible for verifying vehicle compatibility, fitment, and intended use prior to installation. While Forza Motor Works makes reasonable efforts to provide accurate product information and fitment guidance, final responsibility for compatibility rests solely with the customer.

Products that have been installed, test-fitted, modified, painted, coated, damaged, or otherwise used are not eligible for return.

Many aftermarket performance products are intended for off-road, racing, or competition use only and may not be legal for use on public roads in all jurisdictions. Customer is solely responsible for determining compliance with all applicable federal, state, and local laws and regulations.

LIMITATION OF LIABILITY

FORZA MOTOR WORKS SHALL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, PUNITIVE, OR CONSEQUENTIAL DAMAGES ARISING FROM THE PURCHASE, INSTALLATION, USE, MISUSE, FAILURE, OR INABILITY TO USE ANY PRODUCT SOLD BY FORZA MOTOR WORKS.

FORZA MOTOR WORKS SHALL NOT BE RESPONSIBLE FOR LOSS OF TIME, LOSS OF REVENUE, LOSS OF PROFITS, LOSS OF VEHICLE USE, TOWING CHARGES, RENTAL VEHICLE COSTS, STORAGE FEES, DIAGNOSTIC FEES, INSTALLATION COSTS, REMOVAL COSTS, ALIGNMENT CHARGES, TUNING FEES, SHIPPING EXPENSES, FINES, PENALTIES, PROPERTY DAMAGE, VEHICLE DAMAGE, OR ANY OTHER INCIDENTAL OR CONSEQUENTIAL LOSS OR EXPENSE.

TO THE MAXIMUM EXTENT PERMITTED BY LAW, FORZA MOTOR WORKS' TOTAL LIABILITY FOR ANY CLAIM ARISING FROM THE PURCHASE OR USE OF A PRODUCT SHALL NOT EXCEED THE AMOUNT PAID FOR THE SPECIFIC PRODUCT GIVING RISE TO THE CLAIM.

By placing an order with Forza Motor Works, the customer acknowledges and agrees to all terms and conditions contained herein, including all return, exchange, warranty, and limitation-of-liability provisions.

Product Description

Upgrade the fueling capacity of your high-output GM LS platform with the FIC (Fuel Injector Clinic) IS303-1000H Injector Set — a premium, high-flow injector kit engineered to support elevated horsepower ambitions. This set of eight injectors flows approximately 1000 cc/min (≈1040 cc/min at 58 psi) and features state-of-the-art data-matched calibration for smooth, consistent fuel delivery and exceptional drivability. Designed as plug-and-play, high-impedance injectors for select LS3, LS7, LSA, L76, L92, and L99 engines, they deliver improved fuel control and throttle response across the powerband. Whether you’re tuning for higher boost levels, E85 compatibility, or serious power gains, these injectors bring reliable flow and accurate control to your build.

Fitment Notes

  • Direct-fit replacement for GM LS platforms including LS3, LS7, LSA, L76, L92, and L99 engines in compatible vehicles.

  • Designed for engines with original high-impedance ECU fueling systems; suitable for stock and modified engines with proper tuning. 

  • Includes necessary o-rings for standard GM fuel rail fitment; verify fuel rail type on your application. 

  • Professional tuning recommended when upgrading injector size to maintain optimal air/fuel ratio.

Included

  • Eight (8) Fuel Injector Clinic IS303-1000H injectors (complete set)

  • Flow data sheet with individual injector serial numbers and match values

  • Performance-matched o-rings for installation

  • Installation guidance and tuning notes

Product Specs

  • Injector Flow: 1000 cc/min at 3 bar (~85 lb/hr) and ~1040 cc/min at OE 58 psi (~100 lb/hr).

  • Impedance: High-Z (high impedance) — compatible with factory and many aftermarket ECUs.

  • Quantity: 8 injectors (complete set for V8 applications) 

  • Matching: Precision flow-matched with data sheet for tight fuel delivery consistency.

  • Testing Conditions: Rated at 43.5 psi (3 bar) fuel pressure using CF-16B calibration fluid.

Product Features

  • High-flow capacity: Supports significant horsepower increases over stock injectors, ideal for boosted or high-output applications. 

  • Precision matched with Data Match Technology: Each injector is individually tested and flow-matched for consistent performance and easier tuning. 

  • High impedance design: Works with stock GM ECU fueling strategies and many aftermarket engine management systems.

  • Plug-and-play fitment: Includes o-rings and hardware for direct fitment into compatible LS fuel rails. 

  • Improved throttle response and idle quality: Better short-pulse width control and tight tolerances enhance drivability during aggressive tuning. 

  • Lifetime warranty on defects: Backed by Fuel Injector Clinic’s warranty against manufacturing defects.