OMG My Engine is Toast

[El_Diablo]

who cares if its shattered? ive always wanted to see inside of the ports and water passages

[MidnightriderZ24]

i agree totally with what everyone said. the 3400 is a STRONG engine john. i put down 358hp and 365ft lbs on a 100% stock bottom end on 9psi!!!! tune was your problem. guaranteed you were having some detonation and put a huge shock load on the valve train (as stated by others)... better luck next time?

[ForcedFirebird]

John, get off the high horse and let us get the complete lowdown on your complete set-up.

I hate to break the news to you, but you are in the same boat as me. I rebuilt my engine TWICE before I realized that detonation was the culprit. You have to remember that your ECM is going to autamatically pull timing with detonation, thereby masking it.

You have a 1BAR MAP, this means that your ECM can only read potentially up to 14.7PSI ABSOLUTE PRESSURE! That is one atmosphere at sea level, when you add boost over 0PSIG (guage pressure) your ECM is no longer adding fuel to compensate. You would have been better off raising your FP then trying to tune when you can't read past 0PSIG (stock MAP's actually can't read that accurately even). It sounds like you were tuning for RPM only in your BIN files, but who am I?

Those pistons in your car in the pics look like they have at least 20k miles on them, how do I know - because I have had more than one 660 completely apart and can see th wear patterns of these motors (especially gen1's).

You had detonation causing one of the cylinders to detonate, in turn causing your failure. I have been in the same boat as you, but my car could be heard in the kitchen while my wife ws doing dishes, from down the road. I got home with a running/knocking engine and she simply says to me "That didn't sound too good" in an innocent fassion.

I'm not going to sit here and flame you, but it's your own mistake - so take it like a man and get back on the horse with the newfound data you have obtained from your experience, and do it right this time.

If I were you, I would kick your "mechanic" to the curb and start collecting some tools to do the job the only way it's goin to be right - "By yourself".

My $.02 take it of leave it, but if you think you are going to now turbo another stock motor and be any fast, you are fooling yourself. Another motor is going to bite the dust if improper tuning is an issue.

[zofo61]

i think we need more pix

^^X2

I want to see the head that valve came from................

[john_V63400]

The head is shattered, Immean theheads were owned.

Those for the last time are forged Arias dishtop pistons.

[El_Diablo]

i think we need more pix

[kflo 93 gt]

That's what I'm thinking Dave, that head has to be totally dominated...

[Superdave]

those look like stock pistons to me...


Oh the mystery of the flipped valve..

In for pics of the heads, Combustion chamber side. If that valve flipped in the cyl that way, the head should be completely shattered.

[El_Diablo]

or a shock load....

[sprucegagt]

Harmonics

[john_V63400]

Looks like someone had a nasty case of KNOCK. Yes I said KNOCK because dyno tuning in one gear does not simulate WOT while shifting. We all know if you have enough KNOCK, then the weak point in your valve train will be found the hard way. In your case it was the cam pin. Grand Ams are bad for having some high KR readings when shifting at WOT. Proper street tuning would of fixed this issue. Got any datalogs from your dyno tuning? I'd love to see the LTFT readings.

Possibly, but what would make the cam gear just stip out of place?

[john_V63400]

I personally don't think the guys dyno-tuning your engine knew what they were doing...

http://www.60degreev6.com/showpost.php?p=338174&postcount=64

http://www.60degreev6.com/showpost.p...0&postcount=58

that was my bad I misunderstood him

[sprucegagt]

Looks like someone had a nasty case of KNOCK. Yes I said KNOCK because dyno tuning in one gear does not simulate WOT while shifting. We all know if you have enough KNOCK, then the weak point in your valve train will be found the hard way. In your case it was the cam pin. Grand Ams are bad for having some high KR readings when shifting at WOT. Proper street tuning would of fixed this issue. Got any datalogs from your dyno tuning? I'd love to see the LTFT readings.

[bszopi]

I personally don't think the guys dyno-tuning your engine knew what they were doing...

http://www.60degreev6.com/showpost.php?p=338174&postcount=64

When I dynoed my car they didnt believe me when i told them Im missing my MAF cause they said it reads its air from the MAP.
They said usually cars only have 1 source of air volume reading.

http://www.60degreev6.com/showpost.php?p=338160&postcount=58

How do you VE tune a boosted app with a 1 bar MAP?

You don't because you can't.

[ikessky]

Maybe it didn't break solely because of tuning, but it probably had a factor in it.

I hope you find the root cause of what happened here. And I was serious that I wouldn't go back to your mechanic.