Here is an interesting site with info on the history of the SPI block/heads. SPI engines are known for dropping valve seats in the combustion chamber when overheated. The pieces will tear up one cylinder/head and then make their way into the other cylinders by way of the intake manifold.
2003 Ford Focus Silver Sedan LX SOHC Automatic
1997 Pontiac Supercharged Trans Am WS6
Sedan Revolution #135
Last edited by FocusPilot; 09-01-2008 at 09:12 PM.