A lot of time taking a new oem short block and adding forged pistons to it while new is the way to go, especially if you add a huge turbo. Now is also the time to upgrade turbo and change all the rubber hose on the motor. I’d also think about replacing the avcs hard lines as they can have oil deposits or coking that you can’t see. Replace the turbo inlet line as well. You don’t need to upgrade the fuel system unless you have big plans but I did send my injectors to a company to have them cleaned and tested.
Replace clutch pilot bearing and have flywheel resurfaced and also if you haven’t done your fuel lines under intake manifold now is the time. Use only genuine Subaru oem fuel line or it will leak and you’ll have to do the job twice, this happened to me.
I used a new oem short block with standard pistons and added a vf 48 and supporting mods. I also did the TGV delete and used an sti oil pan, baffle and killer bee Pickup.
The expenses can eclipse 5 grand very fast.
I’d stick to the standard block and keep the power goals realistic unless this is a fun car and you have deep pockets. People like joe at asf machine in grand junction Colorado can do the piston swap and advise you. Also don’t forget the heads, I sent mine to ASF machine fed ex and they turned out great.
Lastly a compression and or subasequent leak down test will tell you the current motors health. These cars can run lean under load with factory programming causing things like burned exhaust valves. A simple vacuum gauge test can also show problems if they exist and is cheaper and easier then the aforementioned tests.
Technical Articles: Engine testing with a Vacuum Gauge - at Greg's Engine & Machine
Replace clutch pilot bearing and have flywheel resurfaced and also if you haven’t done your fuel lines under intake manifold now is the time. Use only genuine Subaru oem fuel line or it will leak and you’ll have to do the job twice, this happened to me.
I used a new oem short block with standard pistons and added a vf 48 and supporting mods. I also did the TGV delete and used an sti oil pan, baffle and killer bee Pickup.
The expenses can eclipse 5 grand very fast.
I’d stick to the standard block and keep the power goals realistic unless this is a fun car and you have deep pockets. People like joe at asf machine in grand junction Colorado can do the piston swap and advise you. Also don’t forget the heads, I sent mine to ASF machine fed ex and they turned out great.
Lastly a compression and or subasequent leak down test will tell you the current motors health. These cars can run lean under load with factory programming causing things like burned exhaust valves. A simple vacuum gauge test can also show problems if they exist and is cheaper and easier then the aforementioned tests.
Technical Articles: Engine testing with a Vacuum Gauge - at Greg's Engine & Machine
