Free Shipping on All Wheel & Tire PackagesAuthorized Dealer — 100% Genuine WheelsPrice Match Guarantee on All ProductsExpert Fitment Support — 10,000+ Customers ServedPay Over Time · No Credit Needed with Snap
Select your vehicle to see Oil Pump Shims that fit
Oil Pump Shims for Your Engine
An oil pump shim sits behind the pressure relief spring in the oil pump. Adding preload to that spring raises the point at which the relief valve opens, which lifts the maximum oil pressure the pump can deliver. Builders fit shims when an engine sees more RPM, boost or heat than it did from the factory, or when they want a margin of extra pressure without replacing the whole pump.
We have 1 oil pump shim product in stock, from Boundary. It is the Boundary 89-05 Ford/Mazda BP I4 Shim Kit, which includes shims marked 7/14/21/28/35 PSI and a retaining pin. It is listed for Mazda BP and Ford BP engines.
Confirm the kit is listed for your exact engine before ordering.
Choose a pressure step that suits your build rather than defaulting to the largest one.
Remember that more pressure is not always better. It adds load on the pump drive and can push extra oil where it is not wanted.
Check the result with a reliable oil pressure gauge once the engine is running.
To check fitment, pick your vehicle to see what fits.
An oil pump shim sits behind the pressure relief spring in the oil pump. Adding preload to that spring raises the point at which the relief valve opens, which lifts the maximum oil pressure the pump can deliver. Builders fit shims when an engine sees more RPM, boost or heat than it did from the factory, or when they want a margin of extra pressure without replacing the whole pump.
We have 1 oil pump shim product in stock, from Boundary. It is the Boundary 89-05 Ford/Mazda BP I4 Shim Kit, which includes shims marked 7/14/21/28/35 PSI and a retaining pin. It is listed for Mazda BP and Ford BP engines.
Confirm the kit is listed for your exact engine before ordering.
Choose a pressure step that suits your build rather than defaulting to the largest one.
Remember that more pressure is not always better. It adds load on the pump drive and can push extra oil where it is not wanted.
Check the result with a reliable oil pressure gauge once the engine is running.
To check fitment, pick your vehicle to see what fits.
