Sp3no

iTrader: (1)

I just stripped down a focus T230 black top Zetec turbo engine built by montune that has been run on low boost and standard pistons. It seems that two of the pistons have failed. The area of piston between the piston rings has cracked and actually come away from one piston so when i removed it from the bore the two pieces about 1.5inches long fell out from between the rings. and another has cracking in the same place. What would cause this, too much boost? Also at the top of the rod where the pin is on all 4 pistons the metal has gone vivid blue is this normal. Im not keeping the pistons but was just curious.

GUZZLER

iTrader: (3)

Sounds like it's had a big whack of boost, are there any other marks on the pistons (det, etc)

Sp3no

iTrader: (1)

Piston number one showed a tiny bit of det, do the standard zetec 2.0L pistons have valve cutouts on the pistons just on the exhaust side?

jamie's

sounds badly mapped,
but its prob been mapped fine, and the usuals happened
somebody decided it needed a "little" more boost so whacked a bleed valve on it