Your piston rings didnt fail , they were abbused
The Valve seats are a MAJOR issues with the SPI heads and its a warranty issue Ford slid threw on , Ford knew/has known for YEARS this was a problem and even made THOUSANDS $$$$$$$$ selling haeds to people to fix this issues , I have built dozens of these engines with this failure (dropped valve seats)
The early Escort head which was the 1.9 just before the 2.0 SP was prone to cracking and I know people that made MILLIONS repairing the early Escort heads for cracks another Head Ford slipped through the cracks with
Both of these should of been a recall but wasent because most didnt buy the extended warrantys and once out of warranty there isnt much you can do
The SPI is a POS when it comes to the valve seats
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