ATTN: everyone who has a fliter on the valve cover breather
#61
PCV is connected between the crankcase and IM.
Breather goes straight to the intake.
The reason i put the catch can on the breather side, is because in boost, when blow-by is accelerated, you have a constant vacuum source (1-2~hg.) hook up to the intake. As pressures build up and some boost leaks through the PCV valve itself, it exits the breather line to be recirculated back into the IM.
Since the pcv is technically closed at idle and boost, I don't see that side being much of a deal, and any fumes/spray that gets past the baffle and the valve itself during cruise is easily mixed in the airflow and burns off without issue.
I still propose, since the pcv valve itself is for emissions, the best solution is this:
Breather goes straight to the intake.
The reason i put the catch can on the breather side, is because in boost, when blow-by is accelerated, you have a constant vacuum source (1-2~hg.) hook up to the intake. As pressures build up and some boost leaks through the PCV valve itself, it exits the breather line to be recirculated back into the IM.
Since the pcv is technically closed at idle and boost, I don't see that side being much of a deal, and any fumes/spray that gets past the baffle and the valve itself during cruise is easily mixed in the airflow and burns off without issue.
I still propose, since the pcv valve itself is for emissions, the best solution is this:
i think a friend of mine did this on his 240, i remember because he has a wire type cup holder in his engine comparment holding the can in place
#68
moroso sells beveled 1'' cromo tubes that you weld into the exhaust.
the exhaust flows past and pulls a vacuum in the tube
they include a metal pvc valve that keeps you from pushing pressure into your crankcase (i can't think of a time that'd happen..but it can't hurt)
i ran heater hose from there to my catch can output, and vacuum line from the valve cover to the catch can input
the exhaust flows past and pulls a vacuum in the tube
they include a metal pvc valve that keeps you from pushing pressure into your crankcase (i can't think of a time that'd happen..but it can't hurt)
i ran heater hose from there to my catch can output, and vacuum line from the valve cover to the catch can input
#69
my exhaust is a stainless begi divorced wg 2.5'' pipe -down to a 2.5'' resonated test pipe (with the little pipe welded in) and then (for now) an enthuza racer (naturally aspirated).
hopefully after the holidays i'll have a little scratch lyin' around and will get an enthuza 3''
...
those wily honda guys thought of it first, but there is a long thread on it here:
http://www.honda-tech.com/zerothread?id=1199935
hopefully after the holidays i'll have a little scratch lyin' around and will get an enthuza 3''
...
those wily honda guys thought of it first, but there is a long thread on it here:
http://www.honda-tech.com/zerothread?id=1199935
#70
yeah - we had one on a diesel project car I was working on, and it seemed to blow as much as it sucked, or sucked because it blew. :-) But it wasn't giving us a heck of a lot of suction. I've wanted to do it, it makes plenty of sense - it'll always have good flow since there's at least as much flow as there is in the intake. Maybe I'll thread a nipple or a EGT valve into my lower O2 bung on the DP.
#72
a few caveats:
i don't run a cat, your flow may suffer with one-i don't know what blowby/oil vapor/etc would do to a cat.
if the output of your catchcan is clean...maybe it'd de-smog the blowby?
if carb or the smog ***** catch you with this thing on...i don't know you.
the georgia 'clean air force' guys never gave mine a second glance, but they were busy looking at the turbo hardware.
i don't run a cat, your flow may suffer with one-i don't know what blowby/oil vapor/etc would do to a cat.
if the output of your catchcan is clean...maybe it'd de-smog the blowby?
if carb or the smog ***** catch you with this thing on...i don't know you.
the georgia 'clean air force' guys never gave mine a second glance, but they were busy looking at the turbo hardware.
#73
The Moroso system is only going to work well at high rpm. Been there done that. An electric pump is a good idea. I used to run a Cobra Mustang electric emissions pump to evac the crankcase of my 5.0l engine. Whatever pump is used it has to have a motor strong enough to pull around 8-10" vacuum or it is useless. I think it's 8-10", been a while.
#75
the catch can vent to atmosphere orifice is routed to a port in the exhaust-bernoulli's principle pulls a vacuum as the exhaust gasses flow by and give you a slightly lower pressure in your crankcase.
just like pcv to intake, but it'd work under boost and wouldn't coat your intercooler/ic piping/throttle body/intake mani/etc with oil
on a 'v' engine, this would help make horsepower as the pistons would move down against lower pressure. on a flat crank inline-4...probably not much help there.
i kept my pcv valve on the intake side of the cam cover, just in case there was positive pressure for some odd reason...it'd keep my dipstick from popping out.
just like pcv to intake, but it'd work under boost and wouldn't coat your intercooler/ic piping/throttle body/intake mani/etc with oil
on a 'v' engine, this would help make horsepower as the pistons would move down against lower pressure. on a flat crank inline-4...probably not much help there.
i kept my pcv valve on the intake side of the cam cover, just in case there was positive pressure for some odd reason...it'd keep my dipstick from popping out.
#80
I think there's two desirable functions in the vent setup- 1. release the crankcase pressure and 2. remove the vapors. What the stock system does extremely well under vacuum is remove water/oil/fuel combustion by-product vapor and that diagram doesn't do it nearly as well because the high vacuum is removed from the system. It relies on the crankcase pressure only. In a street environment, you'd ideally have the PCV valve hose as stock to the manifold but with another catch can inline. The vent hose would then vent to air with a catch can inline (or vent to the intake pipe pre-turbo). This way you'd get vapor removal more regularly since the street car most likely sees vacuum as much if not more than the boost.