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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.

Return Policy
We have a 30-day return policy, which means you have 30 days after receiving your item to request a return. To be eligible for a return, your item must be in the same condition that you received it, unused and in its original packaging. All returns are subject to a restocking fee based on item and package condition. Buyer is responsible for paying for return shipping costs. If you need a return label, we will email you a return label and deduct cost from refund. Original shipping costs are not refundable. Special order items are not eligible for return.

Cancellation Policy
In order to cancel your order you must email within 24 hours of placing your order or before your order has shipped, whichever occurs first. Special order items are not eligible for cancelation.

Exchange Policy
We have a 30-day exchange policy, which means you have 30 days after receiving your item to request an exchange. To be eligible for an exchange, your item must be brand new in box. Buyer is responsible for paying all shipping costs to exchange product.

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.