Jay Cartay

iTrader: (3)

Hi all. I've been looking at an ad that says "This car was owned by a mechanic and I have been told that the engine is fully forged with Cosworth pistons etc, but sadly there are no receipts we cannot verify this."

So, being a sceptical type, I wondered if this could be verified, perhaps with a boroscope/borescope or similar?

Ste333

iTrader: (3)

I think it would be pretty hard to tell without physically seeing them! You'll know if it's had a rebuild as most forged builds have very light piston slap noise when idling. Although that still won't verify the type of pistons I suppose....and I would be reluctant to assume it's had a good standard of rebuild without the paperwork or detail.

Jay Cartay

iTrader: (3)

Yeah those are my thoughts to be honest.

ryan51

Had mine checked with a boroscope.assumed to be forged,sent pictures to many engine builders who agreed they looked like forged items.managed to track down a previous owner and got paperwork for a forged build using cosworth pistons.good result!

Steve001

iTrader: (7)

Try and find out where it was done, maybe the builder would have some paperwork?

ossett2k2

iTrader: (9)

I bought a car last year with a forged engine,built by a reputable builder,using cosworth internals,all reciepts present etc.
Engine didn't last long tho,Piston failed and the others had fracture lines so were ready to let go.
You take a chance either way tbh
Read some bad reports regarding Cosworth pistons(after I bought it)
I'm sure some are ok but personally would not use cosworth pistons again due to my bad experience.
I do think the failure was down to bad mapping tho as the Pistons did show signs of det,confirmed when I plugged it in,the det was pretty bad.

Cambs_Stuart

iTrader: (3)

Assume nothing unless you've got paperwork. If they've lost the invoice the only way would be to contact the firm that did the work directly.

gazzawrx

iTrader: (11)

what year and car is it?

cosworth and some mahle forged pistons have a square shaped dish on the crown whereas standard newage sti pistons dont, this should be easily identifiable using a bore scope, that said i believe the earlier classic sti pistons also had a square crown so maybe a bit harder to tell on them.

madwrx

iTrader: (2)

without receipts i would only pay standard car money
-a forged build or just forged pistons?5k miles ago or 75k miles ago???-a rebuilt forged engine mainly only benefits from the fact that it normally includes an engine rebuild at same time. so starting with a zero miles engine again - new oil pump?-new crank?-fresh bearings and clearances?heads refreshed? standard or uprated rods?
without any receipts what pistons it has is irrelevent really. lot more to refreshing an ej20-25 engine than just the pistons.