Boundary Billet Oil Pump Gears for H22 Prelude/Accord

Boundary Billet Oil Pump Gears - Honda H22 (Prelude, Accord & Torneo)

The H22 is one of Honda's great high-revving engines, and that's exactly why its oil pump gears matter. Every trip toward redline is another stress cycle on a pair of sintered powdered metal gears rated around 6,000 PSI. These Boundary gears replace them with billet steel approaching 110,000 PSI yield strength, heat treated for sustained operation above 9,000 RPM, which is the range an H22 actually lives in when you're driving it the way it was built to be driven.

High RPM Is Where Sintered Gears Get Nervous

Honda produces OEM pump gears by sintering because it's cheap and holds tolerance well, but sintered powdered steel is weaker than even a casting, around 6,000 PSI. Sintered metal also fails suddenly rather than gradually. It cracks. And a cracked oil pump gear on a running engine means losing pressure without warning, which on an H22 spinning past 7,000 rpm is a very expensive few seconds.

Billet steel behaves differently. Boundary starts from solid stock approaching 110,000 PSI yield strength, roughly 18 times what the factory gear offers, and cuts each tooth in-house. They developed the steel grade and heat treat with metallurgists, and every gear carries an HT number tracing it back to its material specification.

MartenWear Dual-Stage Heat Treat

These get Boundary's MartenWear dual-stage heat treatment, rated for operation over 9,000 RPM. On an engine defined by its top end, that rating is the point. The dual-stage process builds surface hardness for wear resistance while keeping the core tough, so the gear holds up to the constant load reversals that high rpm puts through a pump drive.

Patented Designs, Flow-Tested, Lifetime Warranty

Boundary holds two US patents covering their gerotor and dual-rotor designs, and validates every design on their own in-house flow bench, testing to 12,000 RPM before anything ships. Machined in the USA, and backed by a lifetime warranty.

Fitment

Who Should Run These Gears

This is for the H22 owner building an engine, refreshing a high-mileage one, or anyone who spends real time above 7,000 rpm and wants the oiling system to keep up. Preludes and Accords with these motors are old enough now that a rebuild is common, and the pump is already off the engine during one. That's the moment to put gears in that won't be the thing that ends it.

Fits: Honda H22, 1991-2001 Prelude, 1993-1997 Accord SiR, and 1997-2001 Torneo. Part number: H22-OPG. Material: billet steel, approximately 110,000 PSI yield strength versus roughly 6,000 PSI for OEM sintered gears. Heat treat: MartenWear dual-stage, rated for operation over 9,000 RPM. Testing: flow-tested to 12,000 RPM. Warranty: lifetime. Made in the USA.