Why Buy A Complete Engine for an Engine Swap?

Why Buy A Complete Engine for an Engine Swap?

Apr 29, '21

In this blog post we go over why buying a complete engine is a better option than buying all the components of the engine separately. This is catered toward those going from a non turbo to turbo application like a 2001 RS getting an 06 STi engine.

Sometimes we get the following question “I have purchased a long block and I’m going to make an engine.” For example, someone purchasing a built 2006 STi long block but not having the other components like intake manifold, wiring harness, hoses, bolts, crossmember, steering rack, etc.


The problem when going down this route is that there are a lot of little things that you need that are all expensive when you have to buy them individually. Some examples of parts that would need to be sourced are bolts, engine wiring harness, hoses, gaskets, inlet pipe, clips, oxygen sensors, etc. When you do the math purchasing these pieces separately ends up being more expensive than just starting with a complete engine. (Click here to see all the pieces with pricing for our WRX into RS swap).


What does iWire Recommend?

We think the best solution is to start with the most complete engine possible and then refurbish it or modify it. If you want to do a built engine for high horsepower like a 2006 STi, then purchase a used or blown 2006 OEM STi engine complete and buy an upgraded longblock for it. The more accessory parts you can get with the engine the better.


Utilizing a more complete engine as a starting point will be easier for you and makes it easier for future shop to work on the engine as well. Shops dread a box of parts showing up from a customer because of the difficulty to figure out what is what and if all of the parts are even there.

Tags: Subaru Swap