Hybrid Racing - Water Pump Port Block Off for K20A2/K20Z

Hybrid Racing Water Pump Port Block Off Fitting - K20A2, K20Z1 & K20Z3

Pull the factory oil cooler setup off a K20A2, K20Z1, or K20Z3 and you're left with an open port on the water pump that has to be sealed. This is the fitting that does it. It fills the oil cooler port cleanly and permanently, so you can delete the factory cooler or run a custom setup that doesn't use the sandwich plate, without ending up with a coolant leak where that hose used to be.

When You Need One

Two situations bring people here, and both are common on built engines.

The first is a straight oil cooler delete. Plenty of builds don't need the factory oil cooler, especially swaps where the sandwich plate and its plumbing are just complexity you'd rather not carry. Pull it off, block the port, done.

The second is a custom oil cooling setup that doesn't use the factory sandwich plate on the back of the engine. If you've gone to a proper remote cooler with its own plumbing, the water pump's oil cooler port isn't part of that circuit anymore. Blocking it off is how you close out the factory system and keep everything sealed.

Either way, this is the small part that finishes the job properly instead of leaving you improvising with a plug that wasn't made for it.

Do It Right, Not With Whatever's In The Drawer

It's tempting to jam something generic in there and move on, but this port is on the coolant side of the water pump, so whatever seals it needs to actually hold. A leak here isn't a minor annoyance, it's coolant loss somewhere you may not spot right away. This fitting is made for that specific port, so it seats correctly and seals the way it should. It's cheap, it's the right part, and it means you never think about that hole again.

Works In FWD Or RWD Swaps

Because it threads into the water pump rather than mounting to anything on the chassis, this works the same in any application. Original car, front-wheel-drive swap, or a rear-wheel-drive conversion, if you're running one of these three engines and you're not using the factory oil cooler circuit, this closes it out. RWD builders in particular tend to end up here, since those swaps often ditch the factory cooler arrangement entirely in the name of packaging.

Fits These K-Series Engines

All three engines share the water pump with the factory oil cooler port, so this fitting works across every one of them, in the original chassis or in a swap.

Keeping Your Oil Cooler Instead?

If you're not deleting the circuit and you just want to convert that port to AN line for a custom oil cooler, you want our -6AN water pump port fitting instead. Same port, opposite direction, one blocks it off and one opens it up to AN plumbing. Pick based on whether that circuit is staying in your build.

Who Should Run This Fitting

This is for anyone deleting the factory oil cooler or running a custom setup that leaves the water pump's oil cooler port unused. Swap builders simplifying their plumbing, track cars moving to a remote cooler, or anyone who's pulled the sandwich plate and now needs that hole sealed properly. Thread it in and cross it off the list.

Fits: K20A2 and K20Z1 (2002-2006 Acura RSX Type-S) and K20Z3 (2006-2011 Honda Civic Si) water pumps with the factory oil cooler port, FWD and RWD applications including swaps. Purpose: blocks off the factory oil cooler port for oil cooler delete or custom oil cooling setups.