When I bought my Twinmax, it came with clear nylon tubes and black rubber tubing for the end, connected by a plastic vacuum coupler.
The rubber tubes were too big for the BMW ports, and the couplers leaked anyways. I replaced all the stock tubing with a smaller diameter (don't remember size) that I was able to get at the local auto parts store.
In addition, disconnecting the power to the meter light inside the Twinmax will reduce meter zero drift to nothing.
If you doubt the meter's accuracy, connect both tubes with a vacuum tee, then pull a vacuum. Meter should read zero (as set on unit) with or without vacuum applied.
Edited by SageRider (04/27/09 09:36 AM)
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