I have a 2008 LY6 6.0 is this the right flexplate for a turboo 400 and an older convertor?
Yes, that is the correct flexplate if you want/need an SFI approved flexplate. But you also have options with the factory flexplates as well. If you want to run an older TH350/TH400 converter with any of these flexplates (TCI or stock) you'll need one of the available spacers (GM or aftermarket) to support the rear of converter by the nub on the back. Lots of good info in here:
Another option is to buy a custom converter built specifically for your application (LS to TH400). This negates the need to run a spacer as the appropriate pilot nub is built into the converter. Mine is a PTC and is application specific. It bolted directly to the TCI flexplate and fits in the pilot hole with no spacers needed.
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