07-08-2020, 06:57 PM
Easy to make: Two equal lengths of 35mm clear acrylic tube, about 150mm long, drill two holes in each tube, about 25mm from the ends. Construct two wooden platforms, two should have two 35mm holes drilled in them with up to a 25 mm gap between them. Next make two more wood pieces of the same shape and two 6mm thick neoprene gaskets, again the same shape. Sandwich the neoprene gasket between one blank piece of wood and one piece with the two 35mm holes and dril ll three holes so they are on opposite sides of the 35mm holes, do the same with the other pieces so you have two identical platforms. Slide the acrylic tube through the 35mm holes and clamp the neoprene and wood platforms either end of the acrylic tubes. Measure the height and cut three lengths of all thread to length, allowing for a nut each end. Screw a nut on each end of the three allthreads and insert them into the 6mm holes, screw on another two nuts, top and bottom of the allthread and tighten until the acrylic tubes are tight enough to form a seal with the neoprene gasket. Then tighten the six nuts so the wood with the Two 35mm holes compresses the neoprene gasket against the top and bottom pieces of blank wood. Cut two lengths of plastic tube and insert into the hole at the bottom of each acrylic tube. Next cut a short length of plastic tube and insert into the two other holes, joining the two acrylic tubes together with it. Fill with water until around 1/3 full. Then insert a jet of some type with a small hole, under 1mm, into each tube. The holes in each acrylic tube should be slightly smaller than the outer diameter of the plastic tube. Slash cutting the ends and heating with a heat gun should make it easy to push through the holes. Connect tubes to the vacuum outlet and start the motor, adjust until water levels are the same. Tip. Connecting the tubes to the manifold will not work, they need to be connected to the carbs, near the venturi. If you have more than two carbs, just add more acrylic tubes as required. Two coke bottles will do the same, or you can buy manometers from auto shops or ebay, they are more accurate than vacuum gauges as the needles on vacuum gauges tend to hunt. Just make sure the water you add is not enough to fill one tube enough to cover the vacuum outlet.