RB25 Forged? ID and Damage

[Tangles01]

RB25 Forged? ID and Damage

Hey guys, I've spent the last while having a decent look trying to fin my precise questions to save having to post, so sorry if this is a repeat but I doubt it, I couldn't find the answers I needed at least. It's 2 part thing. RB25DET (bulk mods not relevant to the question)

A: Can anyone positively identify these pistons form the photo/markings? I have been advised they are a forged piston but cannot find confirmation.

B: The damage near the edge (actually a pop rivet ended up in the motor, don't ask me how). I'm concerned if it were to be used that it could be a detonation site.

Car made (on the current engine) 333 rwkw at 21 PSI. It's a beast. But the engine has developed a knock and I've found some small metallic fragments, although not many, the oil has been in the car for about 35 laps of QR over 2 weeks and the knock has only just started (literally on the last lap) so while it's not a lot, it's not like it's been there long and if it's just started it would make sense to find just a small amount yeah?. So looking at pulling and a rebuild anyway, but have these pistons here already, if they are forged I'd like to use them, but not if it's going to cost me another build later because of that damage. Any help from experienced gurus is very very welcome.

 

It does get some serious use use per this vid:

 

 

 

 

20170425_124931.mp4

[WantGTR]

They look like stock rb25 pistons.

Rebuild. 

/end thread 

[doo doo]

yep they're stock, I've got a couple of spare stock ones if you're interested, sounds like you're in Brissy? 

[Tangles01]

Ok, Thanks guys. The more I looked the more I felt they were not forged. Can anyone confirm my thought about a detonations sight? I assume that piston will need to be binned. Rebuild near certainty, just weigh up up the options now.

[GeeDog]

What does the corresponding part of the head look like?

[GTSBoy]

There's no det damage on that piston.  That's a mechanical impact.

[Tangles01]

I know that's mechanical damage, I was asking if I were to use it it would be a sight where detonation would accord due to the thinner raised area (even if I removed most of it) getting hot. But as they aren't forged I don't think it's worth the risk anyway. If they were forged like I was advised then I would have considered it, pending some feedback.

[GTSBoy]

That would be a throwaway, even if it was forged, on any engine that you wanted to make power out of.