I blew my engine over a decade ago when my fd had boost creep. The cars been sitting so I’m not sure what the condition are now but last I checked the rear rotor towards the firewall had 0 psi while the front still held. Would blowing the apex seal take out the stock twins too? I’m finally going to revive her but just wanted to get a general idea of what I’m into before a shop tears her down.

 

Your story is just like mine was.
Still remember the overboost on I10 right hander on ramp.

I was lucky when I let off seeing needle creeping to 1 bar, yet it still chipped 1mm off of a triangular piece.
Checked my turbo hot sides with a tiny mirror from harbor freight all good,
Was confirmed while disassembling the engine, tiny piece was still inside the housing.
It could, and sometimes it doesn't.

Expect a lot of de-oxidization elbow grease.
I'd suggest doing it yourself, it's not too hard if you have done mods on your car yourself and plenty resources here on the forum and beyond.
You'll know you have torqued all of the bolts right, and you'll know what pieces 'reputable shops' had forgot to put back on with their prior works.

Expect a new fuel pump, de-rusting& recoating of the fuel tank.
If funds are enough, I'd just purchase the new short block.

You will have rubber o ring mark on irons, rear housing will very likely need to be replaced if re-building existing short block.
I'd replace all seals unless you know they're low miles.
Expect to clean the heater core through, possibly a new radiator, your will have coolant gunks on water passages that needs to be cleaned off.

Have a plan for your power goal, boost up, single, monster stud 2 bar etc.
Fuel rails and new injectors and or ditching unnecessities such as AWS are much better done engine out.
Replace FPD while you're there and check solenoids with a vacuum gun.

Best of luck, and may your FD find itself back to the road and track.

 

Thanks man that was super informative! I’m trying to find to short block atm. Ray Crow is still selling them but looks like stock is still backed up.

So if I understand you correctly, your twins were fine and you didn’t have to rework them during your rebuild?

 

Mine was fine, but I have seen turbo hot side chip/bent from others before.
I think it's a hit or miss with unknown probability without enough data. In my case, letting off(closing throttle probably was a main variable) at the moment of over boosting helped.
Even the housing damage was really minor and on exh side irrelevant to the compression side.
It was a big relief as turbo on it was and is new like N3G1.

It's a guesswork until you take it apart really.
I am not a turbo expert but perhaps only CHRA needs to be replaced on either of primary or 2ndary even if it is chipped.
Even when chipped minorly seen people still put them back on driving it.

Chipped piece actually hit the next apex seal on revolution and dented it but did not break it.
Detonation is a force to be reckoned with.

 

I would say a high percentage of broken apex seals exit through the turbo. You will have to do a VERY deep inspection of the turbos to see if they are good. The sides of the turbine blades are what chip when the apex seal piece goes through them and you can't see that with looking at them regularly.

You can get a cheap endoscope off of Amazon or Ebay that connects to a laptop or phone that has a "snake" camera and a light on the end. If you position it JUST right you can see the edges of the turbine blades and look for chipping. You can also take the turbos apart to visually look but that many times just creates more problems - broken bolts, etc.

Dale