Z28Roxy

iTrader: (4)

I don't have my SC yet but I've got pretty much everything else ready to go (built engine, twin disc clutch, dana s60, dual fuel pumps, big injectors... etc) and I've done a search but I can't get much in the way of conclusive answers for what the ADVANTAGES and DISADVANTAGES of crankcase venting for a boosted car (in particular, LT1).

The systems I've seen as I've said are:

Breathers, which get oil mist everywhere.

Evacuating out the exhaust (supposedly doesn't work too well if you have mufflers... I have 2.5 TDs with borla Xr1s, no cats)

And running a catch can setup (requires a vacuum pump, I think).

Anyway, tell me more about the advantages and disadvantages of each setup... and if there are any alternatives.

89ROC-Z

iTrader: (11)

Well the best would be to run a vac pump, but that's $$$. I would run dual breathers off the valve covers with -12 or -10 lines. The breathers that race part solutions sell have baffling inside to get rid of any mist

MIGHTYMOUSE

iTrader: (59)

disadvantages of the stock pcv system are:

-doesnt do all that good of a job at keeping the oil from the intake
-has the fresh air hook up in a spot that would be under boost in FI app.
-factory pcv valve is questionable at holding up under boost
-has hoses y'd together limiting overall flow of the system (cant remember for LTx)
-has no place for the rush of oily blow by to go other than right back into the intake.

disadvantages of exhaust scavenging

-doesn't catch anything
-doesn't work well on anything other than open headers
-blast oily mist directly on your o2 sensors possibly cat converter
-not 'legal' emissions-wise

disadvantages of open element

-oily smell all the time
-negligable crank case vacuum
-open system will effect idle circuit air and tune
-blow by deposits in the oil, shortening oil life

disadvantages of mechanical pump
-cost
-packaging /mounting to engine

i have a few tricks ive figured out over the years addressing nearly all of these. pm me.

edge04

iTrader: (9)

how often do you guys with catch cans empty them?

MIGHTYMOUSE

iTrader: (59)

for me it depends more on when my ocd kicks in than how full the cans get.

edge04

iTrader: (9)

well i just drained out about 10 oz of yellow water. that's after a bunch of dyno runs and 1300 miles. seems to be doing its job i guess. it is only a 1 quart capacity so assume i don't want much more than that amount in there?