OH HOOOOO!!
Sean has jokes for whipping dumpy rides.
Travis did your car run like shit after it was reset ?
It may of idled slightly rough for a moment, but nothing bad at all. HUGE power difference from an ECU reset at times.
Im late to the party but I have to give Wayne some props as well, Wayne does top notch work.
First of all hg is Mercury.
15hg means nothing without a unit of length. The 15mmHg would be the amount of pressure to support the pressure of a cylinder of mercury 15mm high. Millimeters are the standard unit for vacuum as the scale is finite from 14.7-0. You may see pressure in other units since the maximum pressure is infinite.
The pressure in an intake consists of two components, the static pressure and the velocity pressure. A pressure tap that is perpendicular to the flow in a fluid stream will read the static pressure component only. A pressure tap that is parallel to the flow will read both components.
Ryan’s catch can is supposed to do three things.
- Vent crankcase pressure.
- separate the oil out of the crankcase gasses.
- Provide additional differential pressure on the rings.
Even 15mmHg is only 0.290 PSI. This is Nothing. The cylinder has 500+ PSI during combustion (35 bar) to seat the rings. Venting to atmosphere with the catchcan would give him a differential pressure of 500-14.7= 485.3 psi on the rings.
With the added benefit of the catch can he will have 500-(14.7-0.290)= 485.59 psi to seal the rings.
Clearly this massive 0.06% change in ring pressure will not make a difference.
Actually if you had a perfect vacuum, you would only have 14.7 psi additional on the rings, this would only be a 2.8 percent increase in ring sealing pressure. And this pressure does not really translate to a 2.8% increase in sealing. once the rings are sealed, they are sealed. This is why they make low friction ring packages, as the cylinder pressure is far more than sufficient to seal the rings.
The only real purpose of the catch can is to prevent the buildup of combustible gasses inside the crankcase. The best way to do this is to draw a slight vacuum from the intake. YOU NEED TO POINT THE VACUUM HOSE AT THE TURBO. This will provide more vacuum than the static pressure would indicate. (this is how the Moroso unit works BTW)
:thumbup
Maf vs. (MAP*RPM)
The MAF uses the cooling properties of air to estimate the amount of air flowing through it. Since both the Maf and MAP systems require the measurement of intake air temperature i will ignore the temperature component.
Air is compressible, so the amount of air is a given volume is the measurement of pressure.
The Maf is a heat transfer based sensor. The air flows over the hot wire, and cools it. the maf measures the power it takes to keep the ware at a constant temperature. That’s why they are called “hot wire Mafs”. Dense air has more molecules per volume, and cools more. Higher flow rates have more molecules per unit of time and cool more. The Maf has no way to separate the cooling of flow and pressure, but it does not really matter. It knows the total number of molecules the Mass Flow. This is why the Maf is a true Mass Flow meter.
Temperature is an important measurement in this system because it is a coefficient of convection heat transfer.
The MAP Concept:
Your engine has a volume, or displacement. Every two revolutions of the crankshaft it consumes that displacement of air assuming 100% volumetric efficiency. That’s actually what volumetric efficiency is, a measure of how much of the theoretical volume is flowing through the engine.
So at 1 bar, 14.7 PSI you will move one displacement every 2 revolutions. That is a mass flow as well, pressure times volume just like the Maf sensor. Unlike the Maf the MAP system is measuring the pressure directly and assuming the volume of flow based on the RPM of the engine. As the pressure increases the number of molecules increases. At two bar absolute, or 14.7 psi of “boost” the volume of flow is twice that of a naturally aspirated engine. This is why you will hear boost referred to in terms of bar because it makes for easy multiplication of the amount of airflow in the system.
Both systems accomplish the same goal, measuring the mass flow.
The reason that Maf cars need to recirculate back AFTER the Maf is so the molecules the Maf counts actually get to the combustion chamber. if they are lost, the engine will run rich.
MAP cars can vent to atmosphere because the pressure in the system is the same everywhere, and venting only changes the pressure which is actively measured by the computer.
Yessir, I should have put inHg/mmHg in there in truth. “hg” is just my shorthand text for inches of vacuum when I post stuff cause I’m lazy on the keyboard but you’re right because in reality it’s saying “1-2 _____ of mercury” which is retarded on my part. 99% of the people here would never even pick up on the technical typo, but then you’re not in that 99% of those people :lol
For awhile, I thought you left the forums as I haven’t seen you post in a bit. Good that you didn’t 
if im not mistaken, that line thats is hooked up to his turbo inlet pipe goes right into the catch can correct? so then whats the issue?
There is no issue. It’s hooked up correct. I wanted to avoid getting blowby, which I’m doing now. It was setup improperly before.
1320 just blew my mind with all the tech talk btw. I don’t even know how to respond to that. Between him and Adam it’s like two forces try to destroy planet earth, and I’m left with a long stick and a can of SPAM to defend it.
there isn’t one. i think people got bored.
I think people were getting butthurt because Bryan isn’t using a sweet APC valve cover breather filter :lol
I know. 