these turbo vary the veines in the compressor wheel to increase or decreas resistance on the impellar. They get smaller to allow faster spool and then as top end is required they open up to allow more flow. They are complicated turbos and I think they are a little overrated. SCC had a project MR2 where they used one and they said it was better than the HKS turbo they had been using but was not nearly as good as the turbonetics turbo with ceramic ball bearings that they switched to.
Bookmarks