ISR Performance - Side Feed Injectors - Nissan 550cc (set of 4)

Our 550cc side-feed injectors for Nissan 4-cylinder applications, sold as a balanced set of four. The right size for the SR20DET and KA24DE crowd that's done with leaking, inconsistent factory injectors but isn't ready to commit to a full top-feed conversion.

What It Does

Replaces your aging factory side-feed injectors with a balanced set sized for moderate power gains over stock. Every set is flow-matched within 2% variation across the transitional, low, and linear pulse-width ranges, so all four cylinders deliver consistent fuel. Stainless steel internals make these E85-compatible.

Fitment

Fits Nissan 4-cylinder engines that use side-feed injectors. Primary applications: SR20DET and KA24DE (and KA24DE turbo conversions). Verify your factory injector style (side-feed vs top-feed) before ordering, particularly on later SR20DET variants.

Flow Rate Selection

550cc is the right size for moderately upgraded builds (typically up to roughly 300+ horsepower depending on fuel pressure, ECU tune, and fuel type). For higher-power builds, consider a top-feed conversion with our IS-INJK48441004 1000cc top-feed set.

What's in the Box

• 4x 550cc side-feed injectors
• Injector O-rings
• Injector flow data sheet

Product Details

Brand: ISR Performance

Part Number: IS-INJS-550-4

Type: Side-Feed Injectors

Flow Rate: 550cc

Application: Nissan 4-cylinder side-feed (SR20DET, KA24DE, and similar)

Internals: Stainless steel (E85 compatible)

Flow Variation: Within 2% across transitional, low, and linear pulse-width ranges

Sold: Balanced set of 4 (with O-rings and flow data sheet)

Related: IS-INJS-550-6 (550cc 6-cyl variant for RB applications); IS-INJK48441004 (1000cc top-feed for top-feed conversion builds)

Legality: Off-road and competition use only