DeatschWerks 18U-05-0650-4 650cc EV14 Injectors 1990-2005 Mazda MX-5 Miata NA NB

Vehicle Fitment

• 1990-1997 Mazda MX-5 Miata NA (1.6L B6-ZE, All Trims)
• 1999-2005 Mazda MX-5 Miata NB (1.8L BP-4W / BP-Z3, All Trims)

Fitment Notes

• Fits both NA (1990-1997) and NB (1999-2005) Miata generations - mates directly to the OEM fuel rail, intake manifold, and wiring harness with no modification required
• Covers both the 1.6L B6-ZE (NA) and 1.8L BP (NB) engines - same injector body and USCAR connector across both generations
• Does NOT fit the NC Miata (2006-2015) - that generation uses a different injector body; see DeatschWerks 18U-00-0440-4 or equivalent NC-specific part
• Does NOT fit the ND Miata (2016+)
• At 650cc/min, these injectors are sized for high-powered forced-induction NA/NB builds - verify that your fuel system and ECU can support this flow rate at idle and cruise before ordering
• Tuning is required after installation - tuning data is available on the DeatschWerks website
• Not legal for sale or use in California on pollution-controlled motor vehicles (no CARB EO)

Features

• 650 cc/min flow rate - suited to high-boost turbocharged or supercharged NA/NB Miata builds requiring substantial injector headroom beyond the 440cc option
• Bosch EV14 injector body - precision spray pattern and atomization across a wide operating range
• Set of 4 - covers all four cylinders of the B6-ZE and BP inline-4 engines
• Dynamically flow matched to within 1-2% variation across the set for balanced fueling and smooth idle
• Drop-in OEM fit - engineered to fit the stock NA/NB fuel rail and harness without modification
• E85 compatible - stainless steel internals support gasoline, E85, and methanol blends
• Full tuning data available at deatschwerks.com
• Limited Lifetime Warranty

Specifications

• Part Number: 18U-05-0650-4
• Flow Rate: 650 cc/min (61.7 lb/hr @ 43.5 PSI)
• Injector Body: Bosch EV14
• Connector Type: USCAR
• Injector Style: Top Feed
• Impedance: High
• Quantity: Set of 4
• Compatible Engines: Mazda B6-ZE 1.6L, Mazda BP 1.8L (BP-4W / BP-Z3)
• Fuel Compatibility: Gasoline, E85, Methanol blends
• Flow Matching Tolerance: Within 1-2% dynamic variation
• Tuning Data: Available at deatschwerks.com
• CARB Approved: No
• Warranty: Limited Lifetime

Included Components

• 4x DeatschWerks 650cc Bosch EV14 Top Feed Fuel Injectors (USCAR connector)
• O-rings and seals

Product Description

The DeatschWerks 18U-05-0650-4 is a matched set of four 650cc/min Bosch EV14 fuel injectors engineered for the 1990-2005 Mazda MX-5 Miata, covering both the NA (1990-1997, 1.6L B6-ZE) and NB (1999-2005, 1.8L BP) generations. Both generations share the same OEM injector body and USCAR connector, making this a direct drop-in to the stock fuel rail, manifold, and wiring harness without modification.

At 650cc/min, this set steps up significantly from the 440cc option and is intended for high-boost turbocharged or supercharged NA/NB builds where larger injectors are required to support the target power level. Bosch EV14 construction delivers precise atomization with full E85 and methanol compatibility. Every set is dynamically flow matched to within 1-2% and full tuning data is available at deatschwerks.com. Note: this part does not fit the NC (2006-2015) or ND (2016+) Miata. Tuning is required after installation. Not CARB-approved.