ISR Performance - Side Feed Injectors - Nissan 550cc (set of 6)

Our 550cc side-feed injectors for Nissan 6-cylinder applications, sold as a balanced set of six. A direct drop-in replacement for the factory side-feed injectors on RB-style engines, with the flow consistency and E85 compatibility a serious build needs.

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 you don't get a cylinder that runs lean while the rest are fine. Stainless steel internals make these E85-compatible, which opens the door to higher boost or aggressive timing on builds running ethanol blends.

Fitment

Fits Nissan 6-cylinder engines that use side-feed injectors. Primary applications: RB20DET and RB25DET. Verify your factory injector style (side-feed vs top-feed) before ordering.

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). If your build is targeting more power, our IS-INJS-750-6 750cc set may be the better fit.

What's in the Box

• 6x 550cc side-feed injectors
• Injector O-rings
• Injector flow data sheet

Product Details

Brand: ISR Performance

Part Number: IS-INJS-550-6

Type: Side-Feed Injectors

Flow Rate: 550cc

Application: Nissan 6-cylinder side-feed (RB20DET, RB25DET, and similar)

Internals: Stainless steel (E85 compatible)

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

Sold: Balanced set of 6 (with O-rings and flow data sheet)

Related: IS-INJS-750-6 (750cc 6-cyl variant); IS-INJS-550-4 (550cc 4-cyl variant for SR/KA applications)

Legality: Off-road and competition use only