Does anybody have any info on these? I saw one on a 24valve at an auction and it had no numbers on it or anything. The only thing I found out was that its some type of crude vgt setup for twins that never made it to production. Is this true?

 

Is it something similar to the dual compressor wheels on the new Ford Powerstroke? Garrett has been testing the design for a while before they used it on the 6.7. Or are you talking about the little flapper valve that closes off one of the volutes in the turbine housing?