One guy seemed to think that they would still run on a cracked liner to an extent (he has owned two STs with a friend still running his old car). I did not really comprehend how that could happen (I guess it the liner had not cracked through completely!), but OTOH they do seem to respond well to tuning when working right.

At the end of the day most engines have issues upon tuning them . I do seem to recall they can crack liners for a number of reasons but that using good oil and ensuring the breather system is working correctly (they have oil filter assembly issues on the earlier cars) can make things awkward. I am sure on VW forums (well, I know) that their engines seem to sound like they will self combust upon looking at them!).

OTOH metal dowels can't hurt .