ALBUM LINK: Here is a photo album DIY project of rebuilding a 2005 WRX EJ205 motor.



I replaced the rods (by choice) and all the bearings/gaskets/seals/o-rings. Total cost in parts was about $700 plus $200 for a machine shop to deck the heads/block and thoroughly wash them. Nothing catastrophic happened, first startup sounded great! However, I had originally opted to not replace the injector top o-rings, which resulted in the left-side injectors gushing fuel everywhere on first startup. The motor idled fine but created a huge puddle of gas in the shop. Don’t skimp! Do it right the first time. The o-rings are unfortunately about $8 each but definitely require replacing so you don’t have to tear the manifold apart again just to fix 2 tiny little o-rings.

I’m labeling this as a “budget DIY” because you don’t need fancy tools like a Snap-On digital torque wrench or fancy seal installers like I used. Just time, basic tools, space to make a mess, attention to detail, and a willingness to take multiple trips to the dealership for parts. The only parts on the whole build I didn’t use OEM were the bearings (ACL Race) and the timing belt (Gates).