I put in a gearvendors OD last winter , so far I have to say it was well worth it

And you know what else? Shifting at 7000, the rpm drop is about 1500, so the engine runs from 5500 to 7000.Listening to the engine/exhaust noise during a pass is like listening to a snowmobile at full-song. With a 727/904 the rpm would drop about double, or 3000+ rpm. Theres not a lot of hp down there on a sbm.