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Boundary Billet Gear Oil Pump for Mazda Mx5 NA NB

Boundary Billet Gear Oil Pump for Mazda Mx5 NA NB


Boundary Engineering Billet Gear Oil Pump for Mazda Mx5 NA NB

Assembled STAGE 1 street pump fitted with 2 Shim @ 72psi ready to bolt on:


Larger higher flow chromoly billet oil pump gears
Compatible with the LARGE NOSE 1.6L only 

Not suitable for the VVT engine
Machined oil pump housing complete with hardware
High Pressure Oil Pump Seal (o-ring)
Crank Seal (Front Main)

2 Shim @ 72psiraises the relief valve pressure by 10-14PSI. This helps the bearings at the high RPM range gain more support.

  • Technical Spec

    The Mx5s oil pump gears are known to be a weak point. Every time the engine is brought up past its stock redline, or past its factory power level you are pushing a pump that was designed to the lowest denominator using powdered metal casting technology. This process of casting produces parts that are between 5%-10% the strength of 4340 billets. On top of that cast components tend to crack, not bend, so when the oil pump assembly does self destruct its likely to be a catastrophic and sudden failure that can ruin rods, pistons, camshafts in a matter of seconds.

    If you do take the risk of assembling your high performance engine with a powdered metal stock oil pump it still takes sophisticated measuring equipment to ensure the replacement pump you ordered is in specification for your housing. Measurements down to .0005 and surface roughness are both measured very accurately using the Boundary Engineering inspection process. The tools do this step alone are worth thousands, and with this purchase its already taken care of for you by highly qualified machinists.

    • Custom machined chromoly oil pump gears fitted uniquely for each housing
    • Housings are fully de-burred to reduce turbulence and increase flow
    • Blueprinting verification system using signed and dated sheets stating your particular pumps clearances and processes.
    • Cleaned using ultrasonic, air blast, and visual inspection technique
    • Assembled with Teflon® impregnated grease
    • Sealed in air tight heavy mil bags to prevent foreign contamination
    • Relief Valve dis-assembly, blueprinting, and re-assembly
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