What can cause this piston crack? If you cant see well there is a crack on the side of the piston between the first 2 rings, and a piece came off. Fortunately it didnt came off the piston and made no damage to the cylinder. It just had no compression and very much smoke came out of the breather. The engine is a vg30det, cima single turbo. I just had my new poncams fitted and i raised the pressure to 1.5 bar(21 psi). Single turbo precision pte5857 billet. I'm guessing it around 450 hp. So this the limit of the det pistons????

youch!

 

yep mate, id say at 21 psi, your pushing the limits of the stock rods and pistons, with a set up like that and its potential after a tune and tinker, id say its time to get urself some forged pistons, and some forged h-beams. carillo rods or eagle rods. get the crank re-ground and balenced at least.new bearings of course, new arp studs. decent gaskets. all things you might aswell do seeing as youve got the engine stripped.

 

look forward to seeing ur set up alive mate

As I said back in Aussie land the damage has been done by the engine detonating , do a rebuild and get a good Dyno tuner and spend lots of Aussie $$$$. ZX will run at 21psi boost if the tune is perfect and the engine is in good order. Myself I do not run with a boost over 14psi with a Dyno tuned NISTune ECU FITTED.