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Miss shift/money shift

BlackShadow406

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I was doing some spirited driving and when I was going to shift into 3rd gear, it locked out so I went into neutral and missed 3rd and went into 1st at about 70MPH. My tires started screaming so I pushed the clutch in and returned to normal driving. Anything I should be concerned about? 2021 GT 6 speed premium package.
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sigintel

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Possible bent valve if you accomplished more than 8400 RPM.
Light valve strikes can leave witness marks on the tops of pistons that can be seen with bore scope.
Motor will likely run with lightly bent valves, but performance will suffer and valve is way more likely to fail completely and destroy the entire head (new head required), piston (can change a single piston) and cylinder walls(need new engine).

Light valve strikes are really no big deal to dremel buff any sharp edge, rouge wheel, clean, then change bent valve and valve guide and reinstall head.
PITA but way cheaper than new motor.

If piston nasty, you can hang subframe to drop pan and likely avoid pulling motor by just unbolting rod and popping that piston up n out (dremel marks before unbolt for exact reassembly).
 

Cory S

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You won't see a valve potentially kiss a piston until 9000+.....
 

IPOGT

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You won't see a valve potentially kiss a piston until 9000+.....
Would not the rev limiter prevent the rpm runaway?
 

Cory S

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Grimreaper

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With a 3.24 first gear and 3.73 rear and 27.7 rear tire, that's 10,250rpm at 70mph.

With 3.31 rear its 9200rpm.

The dash is not likely to register fast enough to show what rpm the engine was forced to turn.
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