Quote Originally Posted by wbute View Post
My blue wb had the poxy single on it. Factory 4.2. No way it was 2 inch anywhere on the system I don't think.
I think you'll find the engine pipes were 2" - I don't think that changed right up to WB. Here are the Prem's pipes. These are original, I took them off to remove the TH400 to fix the rear welch plugs. Tailshaft on these is 71mm diameter for a reference.

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