Engine blew up 20 miles after 2018 mani+tune install.

[Brico]

Back in June my motor blew 20 miles down the road after installing a 2018 manifold and tune on my 17 GT. Shot a big ass cloud of smoke out the back at 7300rpms in 4th gear. Had some pretty gnarly damage on cylinder 5. I have datalog from 10 minutes before the motor blew (unfortunately I wasn't logging the moment it blew) and was wondering if any of you guys with some tuning knowledge could look it over and see if there were any red flags. https://www.dropbox.com/s/iwgsf3h4ugt42au/log0009.csv?dl=0

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[RacinJason]

What fuel are you using? The last WOT showed your timing over 31 degrees, and that's pretty high. Knock looks fine though, so maybe the timing is fine. The other two WOTs before only go to a bit over 28 degrees. The rpm seem to climb much smoother on the first two, but the third looks much rougher. That may be due to the road you were driving on though.

 

[chagan02]

Man that sucks, sorry to hear that. Gotta admit, that’s a little scary. I’m going with an 18 mani, LTH, and a tune.

 

[Brico]

What fuel are you using? The last WOT showed your timing over 31 degrees, and that's pretty high. Knock looks fine though, so maybe the timing is fine. The other two WOTs before only go to a bit over 28 degrees. The rpm seem to climb much smoother on the first two, but the third looks much rougher. That may be due to the road you were driving on though.

Thanks for the reply. I was on 93 octane. I do remember a hesitation at the top of one of the gears during one of those datalog pulls, like a misfire maybe...but I also remember having some wheel spin so that could be affecting the log too right?

Man that sucks, sorry to hear that. Gotta admit, that’s a little scary. I’m going with an 18 mani, LTH, and a tune.

Yeahhhh...it sucked lol. I should have written out the whole story here because It might put you more at ease. My car in stock form would sometimes puff out white smoke on warm startups since I bought it at 12k miles (blew at 22k). I bought it in the middle of winter so I never really did a warm startup to notice it at first.

A lot of people told me it was normal, just condensation and maybe it was. But I can't help but wonder if it was related. Thing is, sometimes the smoke would come with a pungent smell, which I would not think condensation would cause. Although the timing of the blowup seems pretty suspect being right after the install and tune.

 

[jrsimon27]

There was no knock.
Strange it blew up. The enemy of an engine is knock.
The piston looks cracked when installing the manifold are you sure nothing went inside your cilinders? Maybe it had a lean mixture.

 

[Shifting_Gears]

Ouch!

White smoke is typically coolant. Not sure the likelihood of a failed head gasket at your mileage, but it’s certainly possible if coolant was entering the cylinder that it “locked” and cause the piston to take a crap.

Otherwise excessive timing, lean or debris entering the combustion chamber.

 

[engineermike]

Looks like foreign object damage to me.

 

[familyman]

That's some serious detonation to do that to the spark plug. Maybe some of the debris in the cylinder if from a valve?

 

[Brico]

That's some serious detonation to do that to the spark plug. Maybe some of the debris in the cylinder if from a valve?

I saw there were some track guys dropping exhaust valves...maybe that's what happened to my engine. I only ever got a look at the intake valves, both were in place with one having some scoring

 

[IrishStallion]

Too much timing for 93. I run 31-32 on E85. Who is tuner??

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