Has anyone seen or installed a DynoValve?

[Frank Lee]

Ummm.... OK.

Not seeing how a poppet is any improvement, as the flow, once past the poppet, encounters turbulence like a butterfly valve or the aft end of any blunt body in flow.

Besides, this device is not an intake; it's only for crankcase gasses. I think if there is too much breeze going through the crankcase, separating the oil out could become problematic.

[t vago]

Originally Posted by Frank Lee

Not seeing how a poppet is any improvement, as the flow, once past the poppet, encounters turbulence like a butterfly valve or the aft end of any blunt body in flow.

One way to find out... It's rather tempting to rig something up for my own testing purposes.

Originally Posted by Frank Lee

Besides, this device is not an intake; it's only for crankcase gasses. I think if there is too much breeze going through the crankcase, separating the oil out could become problematic.

See? You burn less gas by... burning more oil!

[Frank Lee]

I doubt breathing through the crankcase is more aerodynamic (less lossy) regardless of valve style. Imagine the flow path through the crankcase vs that of an intake system.

See? You burn less gas by... burning more oil!

Reinventing the Opel Shell Economy Competition Vapor Engine???

[t vago]

Originally Posted by Frank Lee

I doubt breathing through the crankcase is more aerodynamic (less lossy) regardless of valve style. Imagine the flow path through the crankcase vs that of an intake system.

It depends. If overall mass flow through the engine (valvetrain, baffles, possibly the block itself) is low, then there might not be that much in drag loss, even though the engine internals would not be aerodynamically shaped.

In any case, I am not about to pay $400 for a solenoid poppet valve and a $10 microcontroller. That particular aspect of the Dyno-whatzit is what makes me lean toward classifying it as unicorn fodder.

[Frank Lee]

You can figure out how much flow there'd be by multiplying displacement by rpm.

Ex 350 cid x 2000 rpm = 700000 cu in/minute, or 405 cu ft/min or 6.75 cu ft/sec.

[t vago]

Originally Posted by Frank Lee

You can figure out how much flow there'd be by multiplying displacement by rpm.

Ex 350 cid x 2000 rpm = 700000 cu in/minute, or 405 cu ft/min or 6.75 cu ft/sec.

That would be assuming full throttle, right? What is that at 5% throttle?

[Frank Lee]

throttle position irrelevant for steady state operation. well system efficiency has to be figured in too...

[t vago]

See, that's the funny thing about calculating a volumetric flow rate of air. What's its pressure? What's its temperature?

Volumetric flow rate by itself is meaningless when throttling is considered. It's the mass flow rate that actually matters, and if you have a large volumetric flow rate at 20 inHg vacuum on one side of a throttle valve, it's equivalent to about about a 2/3 slower volumetric flow rate at atmospheric on the other side of the throttle valve. In both cases, though, the mass flow rate is the same - it has to be.

[Frank Lee]

All I had in mind when I made my comment was a way to visualize, or get some idea, of how much air is passing or could be passing through an engine. So, can you imagine 6.75 cu ft of air passing through a crankcase every second? I'm thinking, that's a gale force wind! Also thinking there's no way a pcv tube with what- .3" typical i.d.- can flow anything but a very small percentage of that.

It would be like feeding the exhaust pipe into the crankcase, no?

[t vago]

Originally Posted by Frank Lee

So, can you imagine 6.75 cu ft of air passing through a crankcase every second?

No, but then again, that wouldn't happen anyway. To me, letting up on the gas pedal to allow more airflow through the engine using this Dyno-thingy is not the same as completely closing the gas pedal and allowing the Dyno-thingy to completely control airflow into the intake manifold.