850 T5, melted piston 20min after the dyno...

Hey,

I was at the dyno with a customer a few days back, the dyno was ok and we ended with ~350hp and ~55kgm from this 2.3L 5 pistons built engine with a large YUKON turbo (GM5(?))

It melted a piston on the way home, boosting 20PSI

The injectors showed 90% on the dyno - 550cc injectors.

EGT was under control, the WB controller is in side the ECU (VEMS).

Is it just a momentary lack of fuel a severe lean condition ?

Glad to get some feed back on it.

Thanks

Elior

Thats a damage from knock. Have you used a knock detection system for tuning?

I did, I can use a better system (just ordered one)

The surface of the piston is unharmed no knock or detonation signs on it...

Just high temp meltdown...

So cheap ecu... I bet the injectors fit that bill too. Which ones are they?

Perhaps fuel starvation under acceleration . No problem shows on the dyno but on the road ?

Bosch 550cc injectors from S60R 2007...