Improving Your Cylinder Heads with the P-D Valve

At Horsepower Monster, we're not afraid to dive into the hardcore tech because we know you will do whatever it takes to make more power. And we figure that more than a few of you either own--or have access to--a flow bench in order to wring the last bit of juice out of  your cylinder heads. So we wanted to bring you this video series of a new invention that we think has some real benefit in the hands of anyone looking to get more air and fuel into the combustion chambers.

The invention is called the "Pressure Differential Valve," and its purpose is to provide engine builders and cylinder head specialists with pure flow numbers through the cylinder head with the valve in place. Previously, to measure flow through specific areas of a port required inserting a pitot tube into the flow path, which changes the amount of flow as soon as it is inserted into the port--corrupting the data you are working so hard to gather.

To get a more accurate reading of how air acts as it flows through the port, inventor Rick Touchette actually put the pitot tube inside the valve. To state it a little too simply, the device is essentially a valve with a port cut through it. Now you have a tool that allows you to gather a complete picture of flow patterns in the combustion chamber at practically any angle, 360 degrees around the face of the valve, and at any valve lift.

Possibly the best part of the Pressure Differential Valve and the software that Touchette has developed to go with it is the fact that this new tool was developed by guy in his shop looking to solve a real problem. Touchette is a longtime engine builder and cylinder head specialist, and he developed this system because he simply got tired of the limitations of doing things the old way. I got my first look at this new tool when working with Touchette on a magazine story and thought it deserved a more detailed look here.

In Part One we take a look at what the Pressure Differential Valve is and how it works. That's the video up top.

Part Two

Now it's time to have a little fun. We put this new device to the test and compare the flow patterns of a stock cylinder head to a CNC ported head from cylinder head specialist Racing Head Service to see if the upgraded hardware really is worth the money.

Visit RTS Tooling, the maker of the Pressure Differential Valve.

Check out the Printable Instruction Sheet .Inst Sheet

2 Responses

  1. Oh boy...if only it could have been named a "Graduated Orifice" pitot valve. Then the slogan could have been "Flowing with the GO". Seriously, this is a great report on a fantastic concept. Thank you for sharing it.
  2. That's pretty good. We need more ideas like that to bring the funny to the site. :)
  3. [...] Heads for Small Block FordsWhile testing the RTS Tooling Pressure Differential Valve we were pleasantly surprised by the outstanding performance of RHS’s Pro Elite 23-Degree [...]

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