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Air and Fuel› Fuel Injection Systems and Components - Electronic

Racetronix

Disc High-Z Fuel Injector

$51.15 $50.22 Save $0.93

SKU: FJ-SM-51S

Special Order
Special Order
Ships in 4–6 weeks
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Description

The Racetronix FJ-SM-51S is a high-impedance fuel injector designed for high-performance aftermarket applications. It features a disc design that resists build-up and clogging, ensuring a longer service life and consistent fuel flow. The high-speed disc action provides a wider dynamic flow range, contributing to improved idling and quieter operation. Its flat mating surface prevents excess fuel evaporation and deposits. Dynamically flowed and grouped to within 1% tolerance when purchased in packs, these injectors utilize Racetronix's custom flow bench. Testing is conducted with n-Heptane at specific pressures and voltages, with results convertible to gasoline flow rates using a 1.035:1 ratio. This high-impedance injector is compatible with all factory ECM/PCM injector drivers. Grease is supplied to lubricate the o-rings prior to installation for a proper seal and to prevent fuel leakage, aiding in quicker starts. While injectors sold individually (EACH) adhere to the listed factory tolerance, Racetronix offers flow-matched 1% injectors when purchased in packs via the 'Buy In' drop-down menu, ensuring optimal performance and consistency for demanding applications.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandRacetronix
Part NumberFJ-SM-51S
CategoryAir and Fuel
5,000+ Trusted brands
1M+ Enthusiasts
5M+ Parts sold
(760) 282-4645 hello@motormia.co

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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