ACL Orbit High Performance Oil Pump Subaru WRX / STI EJ20/EJ22/EJ25

Since I’m doing my timing belt service I decided I wanted to upgrade my oil pump as well. Fit and quality are perfect and it even comes with a new front seal as well as the small rubber o ring. I appreciate the extra hardware too! Happy to have paid pretty much the same price for an upgraded unit!

the price seems too good to be true and it is. After more research this is just a 10mm housing machined to fit a 12mm rotor. I've read about people getting metal shavings in their oil and no oil pressure for quite some time after startup (for me it was around 5-10 seconds on a warm day and even longer on colder days). The first time priming my motor, just cranking it wasnt enough to get the oil pressure light to go off. Had to turn it on and took around 10 seconds to go off. I've built another motor with an oem 11mm pump and it gets oil pressure immediately. I would recommend spending a little more on an oem unit if you can.

Also I am getting a lot of low load&low rpm knocking which I'm assuming is insufficient oil pressure? Will update once I get an oem unit in

I was very hesitant to try this unit but took the plunge to replace my 12mm JDM pump that has the pressure relief valve issue (unusable, the "piston" seized in the relief channel). Flows well, well constructed, and does not contain any casting flaws as it seems to be a milled item.

This is the best oil pump you can buy. It flows more oil than factory Sti 13mm oil pump. I recommend this oil pump for anyone doing a performance build.