Check this impeller out. I bought it and a housing for my A-trim. It was suposedly an s-trim, but looking at my "street supercharging book" the s-trim doesn't have the little dips on part of the impeller (its completly round) also there is a small stamped R on the impeller.

Now my book might be wrong, and the R might just be a registered trademark thing, or something else. BUt anyone whos opened up an s-trim or r-trim, can you please help me out. Thanks!

-- Joe

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