So I have a 90 turbo TII and I was wondering if I took a picture could anyone tell me if the turbo on the engine is stock? It seems large and I wonder if it is aftermarket (despite it's wear) and wasn't tuned right which caused my engine to blow a rear rotor...if you can't tell from a picture is there a serial number I can look for or anything?

 

Sure, post a picture.

For reference, this is a shot of my stock S5 turbo during my build. A stock turbo will say HT-18-2S on the compressor cover.

 

That is for sure not the OEM turbo. seems like a BNR

 

No, it's a stock turbo in my picture. A T04b compressor housing is much larger.

 

Here is a snap shot on my turbo...it seems larger to me. I wonder if it is aftermarket if it was tuned right and that caused the engine to go early.Then again I have no real support for this idea

 

Im not sure why it turned it sideways, sorry that doesn't help at all

 

A shot from the front would tell me more, but judging from the wastegate actuator, how it's mounted, and the look of the compressor cover, that's a stock S5 turbo just like mine in the pic above.

The only way that could be aftermarket is if the inside of the cover was machined for a larger compressor wheel (ie BNR stage 1). The stock inducer is ~43mm, but T04b wheels up to ~60mm can be used.

 

the turbo seems stock to me. its just hard to tell completely the picture is not as clear

 

Ok, and is there a way to tell if the wastegate actuator is functional? I wasn't able to get it to move any way so I didn't know if that would cause any problems. Ill have another picture from the front most likely tonight.

 

The spring in the actuator is stiff, so you'll have to pull on the arm pretty hard. If you have a small hand pump / bike pump, you can apply pressure to the actuator to watch it move. Just don't apply a ton of pressure, as you could damage the diaphragm. The arm should be fully extended by 6 psi.