Plastic fuel tank inflow tube

[Thomas Smeltzer]

Does anyone have a picture or drawing of a plastic tank uniflow set up where the uniflow tube  is set up that just requires the brass tubing uniflow tube to be rotated to make the tank adjustment for tank height inverted flight?

[Dane Martin]

Here's what I drew up one day. This is for suction based uni flow. If you run muffler pressure, the middle tube only runs to the middle with a little sharper bend to the outside of the tank.

[dale gleason]

FWIW.....As the uniflow is moved up/down, it will move away from the interior sidewall. Put a piece of fuel tubing on the end, cut at a 45 degree angle and it will stay against the interior sidewall no matter how much you move the uniflow.

Good illustration, Dane.


dg

[Dennis Toth]

Tom,
There are several ways to set-up the plastic tanks for uniflow. I have used the two free floating tube approach for piped set-ups; standard set-ups and 4stroke set-ups. In this set-up you arrange the tank with three hard tubes through the stopper. The top tube is longer and goes to the bump in the tank as the vent that is capped after filling. The second is the uniflow line, this line come into the tank about 3/4" and has a length of flex fuel tubing with a clunk tip sized to end about 1" from the back of the tank. The third line is the fuel pickup line that again has a hard tube through the stopper about 3/4" with the flex fuel line and clunk tip sized to end about 3/16" from the back of the tank.

Position the tank with the centerline on the centerline of the spraybar in a full fuse model or at the normal position above engine centerline on a profile (some engines like a Fox 35 like it about 3/16" above the engine CL). I like to have several shims under the initial tank position to allow lowering or raising (for inverter engine installations) to get consistent upright and inverted lap times.

If you are using a suction arrangement install the uniflow open line on the inside of the fuse pointing into the air stream. On a profile put the uniflow vent on a tap that sits above the fuse profile pointing into the airflow (I use a 3/16" strip of 0.012"brass and solder a short piece of tubing to it. Drill a hole at the bottom and use it as a washer under the back mount bolt).

Best,    DennisT