04 wrx blown up. Replacing with oem ej20 shortblock

[Custer175]

So my 04 wrx starting knocking bad a few weeks ago. Im planning on buying a new oem ej20 shortblock. My question is should i do anything with the turbo? It has 90k miles on it, and the last thing i want is for the turbo to blow up and takeout the new block with it. How reliable are these turbos? I autocross the car on occasion,and mainly want it to be reliable. Also what should be done to my heads before installing on a new block?

[SD_GR]

The Mitsubishi turbos are proven units. If it has not been abused it should not need replacement. However, since your block has failed very prematurely, I'd look at the turbo and see if you have any obvious signs of failure (oil seals, shaft play, and so on).

Talk to a machinist about the heads. What should and could be done vary depending on whom you are asking, what the budget says, and your goals.

[Custer175]

The turbo has no shaft play, still feels tight. I only put 4k miles on the car so idk how hard it has been driven. It was tuned with a cobb ap stage 2 (17psi i believe?) for about 3k miles

[JackG]

How did you engine blow? I'm planning to buy an 04 wrx with 94K miles for $10K and I don't want to blow $10K. Are these car reliable?

[Custer175]

Not sure I believe it spun a rod bearing. I was driving the car hard when it happened though so I'm sure that had something to do with it. Not sure on reliability I've only put 4k miles on one lol

[bomoseh14]

lol, I just bought my first Wrx, and it has 90k on it. I'm not an expert but it sounds like too much boost?

[zax]

However, since your block has failed very prematurely, I'd look at the turbo and see if you have any obvious signs of failure (oil seals, shaft play, and so on).

I agree with Spiro. Rod knock is typically caused by some form of lubrication failure, likely oil starvation. Keep in mind that since the oil is shared between the turbo and motor, oil starvation while in boost (from oil pickup failure or sloshing, and this is typically while in boost) will also damage the turbo bearings, shaft, and seals in extreme scenarios. Windage, cavitation, and other internal fluid disturbance may also cause rod bearing failure without affecting the turbo, so it is a gamble. Either way, it doesn't hurt to check.

lol, I just bought my first Wrx, and it has 90k on it. I'm not an expert but it sounds like too much boost?

Cobb Stage 2 maps are set to ~17psi peak boost on the 2.0L with the TD04L-13T. It is normal.