imported post
The first manometer I made consisted of a long narrow board with four 1/16" ID vinyl tubes fastened to it, filled with a quantity of coloured antifrieze. I used aquarium valves for restrictors. It was large, it was awkward, and it was a real pain to calibrate, but the scale was so large it would have been possible to be quite acurate if everything else had been right. The next try was simply four analog vacuum guages with small marsh needle valvesfor restriction. The guages had screw type adjusters to calibrate but they were not a jewelled movement and had such stiction that the needles would not move with the carb adjustment, then they would jump and the adjustment would be too great.
This year I bought a Motion Pro SyncPro manometer (Pt. No. 08-0411) and couldn't be happier. Very easy to calibrate, easy to read, and comes with the neccesary fittings and hoses. There is also the Morgan tune which I am told is also an excellent tool. I paid over $130 at the stealership, knowing full well that I was being robbed but in retrospect it was worth every penny. I believe they sell for under $100online. I think part of the choice may depend on which side of the Atlantic you call home, since if I am not mistaken the Morgan tune is made in the UK.