Flywheel grind

[Phosoup253]

Bought my 05 LGT a while back and immediately had to replace the motor due to a spun bearing. First thing I noticed when I pulled the motor were grind marks on the teeth of the flywheel. The previous owner had the clutch pressure plate and flywheel replaced less than 500 miles before my purchase. I don’t know to much on the specific of the brand and year that was used. 
I’ve read people opting to replace their stock flywheel for an 06+ Wrx being that its not dual mass. Any reason why the 02-05 Wrx are not compatible?

Also noticed the LGT flywheel bolts are difference than the standard Wrx and Sti. Any reason why Subaru did this? 

My car current setup is unknown clutch and pressure plate with a lightweight flywheel using the stock T50 LGT bolts. 
I do hear a chatter at initial start up then goes away and also chatter when I press in the clutch at higher rpm’s. Hopefully I was thorough as possible but anyone has any input on what’s going on? 

 

I
 

Edited December 30, 2022 by Phosoup253

[Phosoup253]

[Phosoup253]

 

 

[rhino6303]

I would replace the flywheel with something known like an exedy tyf001 flywheel.

Definitely replace the torx+ bolts with oem hex head bolts (subaru part number 800610740).

[Rusty9]

well, the only part that touches those teeth is your starter so that would be a good place to look first