The MX-5’s oil pump gears are known to be a weak point in the motor. 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 Carrillo rods, JE pistons, and high performance 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.
This product takes all the guess work out of assembling your motor. Purchase, bolt on, drive, and never worry that your engine’s next red-line visit could send 8000 RPM components into a steel on steel grinding match.
The street/strip is the upgrade to the 91.5-00 and the Race is the upgrade to the 01-05 VVT motor.
All three pumps are interchangeable. The advantage to the higher flow pumps comes about through more mid range bearing support because you will get more oil pressure sooner in the RPM band.For most cars we recommend the street/strip pump. We also recommend 2 shims in the relief valve which raises the relief valve pressure by 10-14PSI. This helps the bearings at the high RPM range gain more support.
Street Pump (Chromoly Pump - NON VVT)
A good all around choice for 90% of the non VVT builds we see. If you're looking to produce higher power levels and increase your limiter this is a safe move for you. With 4340 billet gears you won't be let down.
Street/Strip (High Flow Pump - VVT Compatible)
The assembly starts off with a set of oversize Boundary Engineering oil pump gears. Then the housing is machined to increase flow, and ensure the perfect home for the oil pump gears. The gears fitted are 4140 billets and the housings are machined in state of the art Matsura mills. For this reason, these assemblies are a step above the billet oil pump gears or other "high flow part" offerings. This is a true high flow oil pump, and we have the proof.
This graph shows a 400whp Miata motor powering down Button Willow with the stock oil pump assembly, which by the way, did explode on the driver in one of the straight stretches. The other data plotted is a new high flow oil pump assembly tested at Willow Springs road course. The maximum oil temperature difference between any 2 matching points is just 3*C with many points being less than a half of degree Celsius separated. The same weight and brand of oil were used in each run. This is the same engine and it was rebuilt to the original engines specs, same turbo, same everything, but with the new high flow oil pump equipped. The differences were as much as 18 PSI! The new billet oil pump gear not only protects your engine from exploding stock oil pumps, but also provides up to 25% extra pressure to keep your block together.
Assembly is ready to bolt on with new:
This quick video should walk you through the process of choosing an oil pump for your high performance Miata. To configure and purchase your oil pump please follow this link: https://fab9tuning.com/boundary-engineering-billet-oil-pumps/ We shot from the hip on this video (not literally). The basics of choosing your pump are as follows: Street Pump (Stage 1): NA car, NA built internals, NA high redline, Turbo under 250whp, Turbo with ATi Damper under 300whp. Street Strip (Stage 2): VVT Engine, Oil Cooler, Turbo over 250whp, Turbo with ATi Damper over 330whp, Turbo car with increased redline. Shims?: Add with additional parasitic items on your oil system. Oil cooler - add two. Oil cooled turbo, add additional shim, Oil cooler, Turbo and VVT - 3 shims.
Posted by james annis on Dec 19th 2016
When i opened up the package containing this engine critical part i was staring at the gate of fort knox. This was impeccably packaged, comes with the warranty and article inspection report in an envelope sealed with ribbon and wax stamp. The pump itself was sealed in an airtight bag.
Very happy with packaging, fit, function and turn around.
Posted by Kris on Apr 26th 2016
Packaging, fitment and performance all better then anything else on the market