For complete info on building a "pitot tube" style flowbench, Click Here.
These are my two benches I have or have used in the past. The first bench is a "crude" model. That bench was back around 1998. I have MUCH upgraded since then. The lower bench is what I'm currently using.
This is the bench I first built. Here are the pictures of how I assembled my bench. The picture quality is kind of low due to my cheap scanner but I plan on updating to a digital camera pretty soon.
This picture is of the whole setup.
This picture is just the manometers. The one on the left I use for fuel flow (12-0-12). The one next to that (8-0-8) I use for my testing pressure. The last one is the 40-1 air velocity manometer. It is the silver face rectangle gauge.
This picture is of a fixture I made to test my carburators with. I took an old block and cut it off below the cylinder. It is ported like I port my engines. It has both valves and springs installed and I have the intake valve set at .233" opening with a nut under the intake valve stem. This fixture can also be taken off and a regular block mounted in the vacuum intake to test a block, carb, and head in as raced condition (which is important)
I have upgraded my flowbench a little. I still use the same gauges but I am now using a "flow surge equalizer" box. Basically what that does is we use a large box between the carb or block that we are testing and the vacuum source. This tank takes the bouncing out of the gauges. Well, not all the bouncing but it makes it a LOT easier to work with. The pump on the front that is being used for the vacuum source is a jacuzzi pump/air blower. The valve in the upper left corner is the flow control valve used for calibrating the test results to the "test carb". Jason Crossley built or had the box built and Tracy Covil ended up with it, I then took it off of Tracy's hands when he no longer wanted it.
Two different views of the new bench.
Here is the adapter I use for flowing blocks. It stays plugged off when just testing carbs.
This is the adapter used for the Raptor Carbs.
This is the pitot tube assembly and setup I use.
This valve is used on the air output side for calibrating the flow to the test carb at each startup to make sure we are comparing the same numbers every time.
You can reach me at phinishline@yahoo.com for comments, questions, and suggestions.