Crank case vent
#1
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Crank case vent
I am probably over thinking this, but better safe than sorry. In my searches I have found that I should use a geniune Mazda 88 323 turbo pcv valve. My other question though is the left side of the engine breather. Does it matter how close I mount the fitting to the turbo? Or do I want to keep it as close to the MAF as possible? Thoughts?
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#5
...actually...would there be any disadvantages to going VTA on both sides of the valve cover and block off the PCV port on the intake manifold?
#6
Going VTA will prevent pressurization issues like shooting the dipstick through the hood, right? But couldn't it also be a major boost leak if the PCV goes bad?
...actually...would there be any disadvantages to going VTA on both sides of the valve cover and block off the PCV port on the intake manifold?
...actually...would there be any disadvantages to going VTA on both sides of the valve cover and block off the PCV port on the intake manifold?
#8
there is one thing that I think you guys are over looking here. by placing that second breather on the exhuast side in the inlet tract you are effectively creating a vaccum in the crank case. which helps to reduce pumping losses, helps the turbo drain and can help to curb oil burning issues. I've seen many a guy with a turbo having to put a restrictor in the oil line to try to stop oil getting past the seals when simply routing that vent to the intake would stop it and give your turbo more oil. there is a reason race engines often use vaccum pumps to increase H/P. it works.
here this was taken from GZ motorsports website:
"All engines create a certain amount of "blow by" (leakage of compressed fuel and air past the rings into the pan area). The "blow by" airflow created creates pressure in the crankcase, the vacuum pump "sucks" air out of the crankcase with its "negative" airflow. The net difference between the air low being "sucked" out and the airflow being "blown" in by blow by yields vacuum. If the airflow being "sucked" out is less than, or not much more than the air flow being blown in, the vacuum pump is not creating enough "sucked" airflow to eliminate pressure in the crankcase or to create adequate vacuum to not only stop leaks, but to create horsepower.
Typically smaller engines generate less "blow by" and don’t require as "big" of a vacuum pump as large displacement engines. However the addition of low tension ring packages, power adders such as Nitrous Oxide, Alcohol, Blowers or Turbochargers (and the ring and piston types, clearances and modifications that go with those power adders) will increase crankcase pressures requiring either a "larger" pump or to spin a "smaller" pump slightly faster. The following guide is based on our experience of testing vacuum pump airflow rates and typical crankcase pressures found in racing motors. "
now in theory your pcv will do this, but when in boost it quits and that is when it is most important .
here this was taken from GZ motorsports website:
"All engines create a certain amount of "blow by" (leakage of compressed fuel and air past the rings into the pan area). The "blow by" airflow created creates pressure in the crankcase, the vacuum pump "sucks" air out of the crankcase with its "negative" airflow. The net difference between the air low being "sucked" out and the airflow being "blown" in by blow by yields vacuum. If the airflow being "sucked" out is less than, or not much more than the air flow being blown in, the vacuum pump is not creating enough "sucked" airflow to eliminate pressure in the crankcase or to create adequate vacuum to not only stop leaks, but to create horsepower.
Typically smaller engines generate less "blow by" and don’t require as "big" of a vacuum pump as large displacement engines. However the addition of low tension ring packages, power adders such as Nitrous Oxide, Alcohol, Blowers or Turbochargers (and the ring and piston types, clearances and modifications that go with those power adders) will increase crankcase pressures requiring either a "larger" pump or to spin a "smaller" pump slightly faster. The following guide is based on our experience of testing vacuum pump airflow rates and typical crankcase pressures found in racing motors. "
now in theory your pcv will do this, but when in boost it quits and that is when it is most important .
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