Correct,, moving pistons doesnt create negative pressure in the crankshaft area becuase as 2 piston moves down 2 moves up and it just pushes air around. On the piston head side negative pressure is created as when tb is closed at idle or coasting and piston moves down it will pull air but as no air is supplied by the tb,, restricts pistons movement thus creates engine braking thus the device breather filter supplies air to the engine and relieves the pistons of negative pressure and lessen engine brake

I think it is a device to reduce engine braking but as engine braking is a useful feature of a car it might draw negative criticism so they dont want to expound the purpose of the device in its description,, at idle it also leans the afr and they dont want to tell potential customers that there is a small bad effect of the device into their cars so they also left that fact of the desription of the device

 

Hum... taking what JJJ said, the PCV is a check valve. The T-rev is a check valve with breather filter.

Now, that said... all I can picture is slightly higher pressure in the crank case... and potentially one really dirty breather filter.

Firstly, the filter will get dirty by nature of what would be typically flowing through there... and that is air mixed with vaporized (or atomized) oil and gas. On the occasion that the TB closes most of the way, the air would be pushing from the intake side through the filter, but that doesn't negate the vaporized oil and gas already in the tube.

As for the pressure... the thing about the factory PCV is, it actually opens due to two forces (though not necessarily always at the same time). They are positive pressure in the crank case due to blow by and negative pressure on the opposite side of the valve due to vacuum of air pulled into the engine through the intake system (which the PCV is now part of). It isn't really much, but whatever little it is, is how much less the crank case pressure needs to increase to open the valve. Hence, it's all slight.

If there's a breather filter right next to the check valve, as is the case with the t-rev... then there isn't any vacuum on the intake side to pull open the valve. Any vacuum created by the engine is relieved by the air pulled in through the filter. So, to avoid increasing the pressure in the crank case over the factory setup, the valve has to be setup with a softer spring that takes less pressure.

Of course, that whole part about pressure was already mentioned by CyclingFit... https://www.fitfreak.net/forums/2nd-...ml#post1422377

How does the device allow air into the engine?

For allowing air into the combustion chamber side, the PCV tubing it uses, connects to the intake "in front" of the TB, on the air box side, not the engine side. And that means its being blocked from going to the engine by the TB.

For allowing air into the crank side, the check valve itself closes, which prevents air from getting in the crank case.

Both are indicated by their very own diagrams. And neither of which allows the t-rev to alleviate any negative pressure.

In the end, the t-rev doesn't seem to make sense to me. At best, it looks like a PCV for cars without PCVs. But like I said, I'm a novice when it comes to cars.

 

The filter is to be cleaned regularly

Crankcase pressure builds up at spirited driving only and blowby geting around the piston rings getting to crankcase creates pressure in crankcase and pcv valve opens to release it,

The device is installed at the pcv line to the intake manifold not the egr line to the airbox. Negative pressure is made when tb is closed at idle or coasting by the pistons as the pistons move down to pull air but struggles as tb is closed the breather supplies air to let the pistons move freely

 

At idle you can hear the filter is sucking air to the engine and the hose to the intake manifold collapses as it sucks air and it reverts to its normal shape at engine off

 

The hose should not collapse. You should change the hose

 

If it is installed at the PCV line, then you have 2 in line Check valves serving the same line. Why do you need 2 check valves for the same line?

 

It would seem that having 2 check valves each located at 1 of the line or located on the same line does not help in letting the engine breathe freely as intended by the device.

My suggestion is to Leave the PCV line alone to do it's job using the OE PCV valve. And widen the Breather hole and installing a simple filter. That will allow the engine to really rev freely.

The downside is that non-metered air will flow into the engine causing a lean condition.

But I'm not a Race car engineer so what do I know?....................

Thanks for all the replies. At least we discussed and learn something out of this.

 

You cant widen the intake manifold hole as the more air it allows to enter will make afr very lean

Epman pcv valve version is designed better because it only has a tiny hole suspended in a long reed protected by three flanges from some pressure saying that theyre pcv lets flow better versus the oem pcv that has a large round hole making it slower air speed to expel blowby and also being pushed back by intake manifold air pressure making it perform blowby dispersal slower than epman or jsracing device

 

Hi,

No. Not widening the air intake manifold hole. That should be plugged up.

Widen the hole at the rocker cover side where the Blowby is flowing.

 

Update: as i changed the intake manifold hose to epman to a thicker hose,, it made suction better and collapses now my pcv to epman hose,, i detached pcv hose to device and got surprised on how much blowby reached the device and covered the inside of the hose. Also found out the filter is one way as well,, it just lets air in and wont let blowby escape the air

 

I was assuming there will be less engine brake with the device relieving the engine of negative pressure but tried to be in gear downhill and still engine braking is strong,, dont know if the device has really small hole to fill the engine with air or my device hole is clogged

 

try to "loose" the spring to max loose settings, and see if that makes a diff? works for me, I feel like I can coast down big hills faster now and it feels like I have less engine braking (ymmv, I have a GK5)

 

did that already,,put it to max opening. but i like that i have better fuel avg now

 

Honestly speaking,, not sure if i feel its effect but it only adds little hp so its really hard to notice it,, but it sometimes prevent my car from stalling,, usually when i get careless clutching the car will just stall but now if i make a mistake the car will sometimes not stall as the device supplies some amount of air it keeps the engine firing when normally itll just die as it ran out of air,, maybe i can also share that it probably improves acceleration as it supplies more air to the engine it launches faster than before

 

Your car cannot run out air. Even if you’re fully off the gas pedal, some air should be going to the engine to maintain at least idle speed. Whether the throttle body is actually sealed tight when fully closed is another matter.

If Your car is stalling out, then you need to press harder on either the clutch or gas, period.

Honestly, I think this has all gone into the realm of either placebo or things that shouldn’t be happening.

 

When clutching i dont press the accelerator and that mean tb is almost closed,, if the car is inclined or wheel is wedge to a stone,, idle rpm will just stall the engine as not enough air is inside the engine to overcome a slope,, but after the install i dont stall that as much as before

 

shouldnt stall, PERIOD.

you prob have a bigger issue, non t-rev related




back on topic, I gotta say the placebo effect is strong. I do feel like the car has better rev's. no dyno to prove my claims tho.

 

Why shouldnt it stall,, are you driving a manual car 1.3 engine like mine? Shouldnt conclude if your car isnt like mine

 

Double post