Prochargerri

I had a piston break on the dyno the other day. I was wondering who is responsible for paying for this. Is it the shop that put the engine in last year? The shop who retuned it prior to this dyno or is it the shop who had it on the dyno? They said the pistons that were put into my engine could only handle 8psi and with the upgrade in my supercharger, it was running 15psi.

mfj

honestly, no one is gonna take responsibility. and u wont really be able to sue. pistons are never rated at what psi it can take. The tuner can argue that the motor was never assembled correctly. the shop that built the motor can argue that the tuner ran it lean on the dyno. or both shops could just say that u drove the hell out of ur car, and it was abused, so the motor expired. its a lose lose situation. i had been in the same exact situation as u, and i got no compensation. the only suggestion is to find a shop u trust, make sure u know the limits of the motor u buy, and have that same shop tune the car.

Prochargerri

Yea I figured that I was going to pay for the damage and none of the 3 shops would take responsibility. Thanks....

2002GTAUTOVERT

EDIT: Other guy answered first

contentsunderpressur

The stock pistons can handle 10 lbs of boost no problem with a good tune. If you broke a forged piston with just 15 lbs then you need a new tuner.It most likely broke due to detonation. Did you ever notice a sound like marbles in a tin can coming from the motor?

mfj

but still cant blame it on the tuner, if the motor was never balanced and blueprinted correctly by the builder, then the tuner might have no fault whatsoever. really hard to tell or blame anyone.

contentsunderpressur

If the motor wasn't balanced properly you would have known it from the first time you started it up. Your piston did not hit the valve but yet a chunk broke off of it. Every engine I've ever seen fail due to detonation had pieces of the piston broke off from the extreme heat and pressure from the engine detonating. Maybe it was just a bad piston from the start, I have seen that before. Look at the rest of your pistons. They'll show tell tell sighns of detonation as well if that was the case.

mfj

agreed. remove ur heads and the pistons will tell the story. but still, detonation doesnt only occur because ur running ur motor lean.
too much heat in each cylinder+ boost+ too much timing =Boom!

Prochargerri

Thanks for the comments. I hope to get the car back soon.