Does anyone know where one can purchase Tall Valve covers for 1.6RR trouble free clearance?

What RR's add the most HP?

 

LT4 covers seem to be the most popular for extra rocker clearance, depending on what rockers you get, they will work with stock covers. There are only a few, maybe 5 at the max differnt styles of valvecovers for LT1s with the dent in the passenger side cover to clear the alternator. If the alternator was relocated you would have your choice of any aftermarket centerbolt valvecover