My bugeye is now at 113k miles with somewhat low compression in one cylinder. Still drives fine. My only mods are an uppipe, catless downpipe and a road tune. My plan going forward is to replace the short block with forged pistons. Once that is done I'd like to upgrade to a VF48 turbo, STI intercooler, Walbro pump and better injectors. Then a tune. I'm curious what folks think of that, and if I can accomplish all that for around 6 grand.
If that's all you're planning to do with it you would be A LOT better off replacing it with an OEM shortblock from Subaru than putting forged pistons in a rebuild.
You would never make enough power with that turbo to cause a problem with the stock pistons. If you put forged pistons into a new OEM block then you would be using "drop in" pistons, which you would have no way of controlling piston to wall clearance. Forged pistons call for 100x greater PTW clearance than OEM pistons. This means the cylinder walls and pistons will wear out much more quickly.. not to mention using drop ins you probably won't be at the .0035" they call for, and there will be nothing you can do about it. A properly maintained OEM shortblock should last 200k+ miles if it's not beat on. Forged engines typically won't last more than 30k.. and I don't know if I have ever seen one surpass 60k.
Also consider the fact that the chance of assembly error will be 1000x greater having Joe Schmo put your engine together as opposed to Subaru themselves.. and most engine builders outside of Subaru will offer little to no warranty.
You would also make less power, get worse fuel economy, have greater blow by, and worse emissions with aftermarket forged pistons opposed to stock. It just doesn't make sense to do to a car that's not being pushed beyond 300whp.
Thanks MF for that thorough explanation. I will stay OEM, yet I wonder why so many people talk about forged pistons like they're the killer app for Subies. Aftermarket propaganda maybe.
Lots of people have no idea what they are doing. Those are also the same people pouring into the forums complaining about how junk their car is and how bad the manufacturer is and their stupidity alone blew it up
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