72vega383

hi I have a 72 vega with lm7 5.3 swapped. I have had the car running but came to realize yesterday that my pcv system is not hooked up properly. looking at the motor there is no pcv valve or catch can. The intake is a truck intake that has been shaved with the map relocated to the rear under the brake booster fitting.

if someone can post up a quick diagram of how the pcv should be done I would really appreciate it. the motor is a 2004 with a dbw throttle body.

I could use any help I can get with this as I don't quite even know where to start. all the evap, egr and other emissions are removed.

thanks!

72vega383

Anyone?

1964SS

iTrader: (1)

google search lm7 pcv or ls pcv for images. you'll find a ton of them.

72vega383

Yes but non of them show routing with the Pcv removed from the shaved truck intake.

reedld

iTrader: (7)

if you removed the PCV port on your truck intake, you will need to use the LS6 valley cover or a catch can.

72vega383

ok. do you have an idea how I can route it still though. there are so many ports on my throttle body and I am not sure if they will get used or not as most of the diagrams don't show. its a stock 5.3 dbw throttle body and my drivers valve cover has one port at the back, passenger has one at the front. throttle body has 2 at the bottom and one in behind and on the drivers side of the block near the valley cover there is another port. confused

reedld

iTrader: (7)

google PCV systems in LS- basically both valve covers will vent to the PCV valve. On the early LS1 intakes, it went to the intake near the TB. I was getting a little oil inside the intake so I did the LS6 valley cover mod. This mod ...if any oil does blow by...goes back to engine, bypassing the intake. I have a 06 Silverado with a 5.3, I can look at my system and let you know for sure. I doubt it is much different than your 2004 BUT you removed the PCV port on your intake. You may want to post up a pic of your intake. I also suggest you check out the LS6 valley cover mod, you may want to go that route .

72vega383

Intake




Drivers side valve cover port




Crossover going into bottom of throttle body




Other end of throttle body port goes over top of manifold and back to drivers balance cover port




Passenger valve cover port goes to top of throttle body port





This is how I have it routed and I ran it like this but don't think it's correct as from what I understand the pcv valve was in the intake that I shaved. I've only run it for a few minutes at a time in the shop but don't want to drive it unless it's correct. Thanks alot

1970camaroRS

iTrader: (8)

These are not part of the PCV system at all. They are coolant steam recovery ports. Absolutely do not run these to the PCV system. They go to the radiator.

72vega383

Oh wow thanks for pointing that out I knew something was strange about that. so I guess I can run that into an overflow bottle maybe?

From what I gather I think the drivers valve cover has a fixed orfice pcv in it so I would have to run that line to the top of a catch can and one out the top of the catch can to port behind the throttle body and the passenger valve cover port would go where? In the tube before the throttle body after the air filter maybe?

brawls43

Don't run it to your overflow bottle, check this thread and search steam port for some others. There are lots options for where to run it. Radiator, heater hose, water pump, etc. Do whatever fits your build best.

Passenger valve cover port runs to any port after the filter, before the MAF and throttle. Its just filtered make up air to balance crankcase pressures.

72vega383

Ok great I'll have to do some reading. So that being said the drivers port into a catch can and the line out of the can would go to the port behind the throttle body? Do I need a pcv valve anywhere else in the system or just rubber hose?

Thanks again!

truckdoug

iTrader: (25)

in the drivers side valve cover port there will either be a restrictor or a check valve.

Doug G

I just tied both valve covers to a catch can with a breather, and added a filter to the oil cap.