Boundary High Flow Anti-Cavitation Oil Pump Backplate for Mazda MX-5 NA NB

£127.99 inc. VAT

Improve your stock oil pump, maximise flow.

Available to order — 1 overdue from supplier

Take your standard oil pump, throw in a set of boundary gears (checking tolerances of course!) and bolt it back together with one of these and get near stage 2 performance for considerably less.

We took the standard BP backplate and threw it away. This new pump backplate was redesigned from the ground up to be better in every way. It starts with the way every motorsport component should be, carved from Chromoly Steel billet. From there we added an all-encompassing flow package to reduce cavitation and aeration of your oil. All BP motors will benefit, but those running more then 7500 RPM will see improved bearing life and oil pump life that a properly designed backplate will give them.


  • Intake volume increased by 80% reducing fluid velocity, pressure drop,?and cavitation.
  • Intake port 3D contoured to help fully charge the gerotor’s mesh further reducing pressure drop and cavitation effects in the teeth.
  • Exhaust port volume increased by 20% decreasing pressure loss from flow exiting the gerotor.
  • Port areas tightened to add flow direction to the fluid and rigidity.

Please note this backplate does not work with VVT oil pumps


Additional information

Shipping Weight 0.27 kg
Shipping Dimensions 23 × 15 × 4 cm

Boundary Engineering


Mk1 (89-98), Mk2 (98-05)

Warranty information

Warranties cover defects in materials and workmanship only. Warranty is for replacement of a similar product, repair of the original product or refund of the purchase value only and excludes all labour and incurred charges including towing, fitting, inconvenience, and purchases of other manufacturer's products. The warranty is good for the period stated in the additional info tab from the date of purchase. Mileage warranties are for road use only and proof of mileage is required. Products must be installed by an independent experienced professional mechanic and the suspected defect must be present at the outset. The warranty does not cover damage caused by incorrect installation, failure to comply with the maintenance requirements of the vehicle, processing or otherwise changing the product, ordinary wear and tear, or any other external influences. Warranties are invalid if the product is used for racing, rallying, drifting, track days or any other form of motorsport or competition. Please refer to the manufacturer's own warranty documentation for more information.

Making a warranty claim

Proof of purchase receipt showing the date of purchase, proof of mileage at installation, proof of current mileage and invoice of the work undertaken by an independent experienced professional mechanic must be supplied along with the returned products for a warranty claim to be considered. If your vehicle needs to be used whilst your warranty claim is considered replacement parts from the same manufacturer should be purchased through BOFI Racing. In the event of a successful warranty claim, we will refund the card that was originally used to purchase the replacement parts, in full or in part depending on the nature of the claim. BOFI Racing reserves the right to make full or partial compensation at its sole discretion depending on the condition and mileage use of the returned suspect parts. For example, if you have used the part for several thousand miles before a defect is noticed, only partial compensation may be offered.

Make Model Year
Mazda MX-5 I (NA) 1989 - 1998
Mazda MX-5 II (NB) 1998 - 2005