Mike, try

http://www.redlineoil.com

Also, you need to run a 20W50 oil with Mahle oil filters. These filters
have an internal spring pressure that keeps oil pressure in the oil
galleries of the engine after shutdown, which in turn keeps the
hydraulic lifters on the WBX engines pumped up so you don't get valve
clatter on a cold startup.

John Rodgers
88 GL Driver