Tommy42088

Transmission eta Wednesday, should be able to get in it next weekend. How are you guys running catch cans with 5.3 ? Mine is ran off the the 2 valve cover ports and nothing goes into my catch can. Also I had my oil cap had one with an air filter on it at the time and I added a normal cap that in a sense closes the crank case. Should I have done that or left the filter?

C5_Pete

iTrader: (8)

As long as you have a catch can, close up the oil cap.

ddnspider

iTrader: (26)

I vent both covers and the valley and done.

C5_Pete

iTrader: (8)

I vent both covers and have a pressure sensor in the valley cover.

Tommy42088

How would I do that though? My valley cover doesn't have a port on it. I just have the 2 ports on the valve cover. 1 is going in and the other going out. Technically nothing is venting the way I have it that's why I ask about the air filter on oil cap.

C5_Pete

iTrader: (8)

For your setup, you probably don’t need to.

I removed the valley cover, drilled and tapped a hole for 1/8npt and screwed in a 1 bar sensor. It’s wired in to my Dominator.

Tommy42088

Passenger side going to out and see no vent on the valley



Driver side going in

Tommy42088

so should i leave the air filter on the oil cap then? Only reason i took it off is because i did notice it would make a little of a mess, not much but just a little oil. I do have port on the bottom of my intake and I also have a distribution block. Could either of those be an option?

C5_Pete

iTrader: (8)

No sir. No need to over think your setup.

a line from each valve cover to the catch can is good. And no vent on the oil fill cap.

the only reason I monitor case pressure is because I’m an all out race car build pushing it to the limits.

Tommy42088

ok awesome so technically nothing is vented that way, that's okay?

ddnspider

iTrader: (26)

The vented valley is if you have an LS6 valley cover. The simplest and easiest is venting both covers or the DS cover and the oil fill.

Tommy42088

ok I'll put the filter back on then, i guess i put a catch can for no reason. Doesnt seem to do much.

Tommy42088

Can't lie I'm second guessing what to do because you are telling me opposite, one saying vent and one saying no vent

ddnspider

iTrader: (26)

You EITHER run a catch can with no vent and such it back into the intake, or you vent your valve covers and don't need a catch can. Sole complain they smell oil vapors when they vent. I've never noticed that so it's really personal preference.

Tommy42088

ok I got it so I'm asking can I vent back into my distribution block or on the bottom of my intake I have extra ports i could put an npt fitting into and if i go that route do i t both valve covers together and put them into the in side and obviously out would go to the intake or do I only put 1 side into the in side and vent the other?

ddnspider

iTrader: (26)

A 3 port catch can would give you 2 in's and 1 out. Otherwise you have to tie the 2 input lines together into a single in side. You can have a line out of the catch can into the intake or a line out of the catch can to a breather.

Tommy42088

that's what I needed to know, I'll t the two lines together then and get an npt fitting and run the out side into my distribution block.

GMCGreg

Gotta be careful using the stock Pcv nipple DS rear as the is only a small hole inside ( can't remember the actual size ) what I've done is drill that out with the largest bit the will fit inside the nipple then fit a gen1 sbc type pcv valve using a couple pieces of different size hose - easy. Have to be very careful drilling as you can damage the baffling when it goes through the restriction. 3 port catch can with 2 check valves , -6 hose . Every body is saying-10 hose and vented can or fill port but this has been working great . Could be some air filter restriction is giving a vacuum pull on both covers when in boost . Lot of variables, power level and ring gap have got to be big factors

Tommy42088

I was going to put a t between the 2 valve cover ports and connect then together and then put that on the in side on the catch can and them coming out of it would run into my distribution block and my can doesnt have a filter. It will be a closed system the way i was going to do it. Maybe my pvc is different or been changed then because mine definitely has a big enough hole for vacuum to easily flow. I just originally had 1 valve cover going in and 1 going out and my oil cap had a filter so I had no flow going through the catch can and my filter would get a little messy at times and I did smell it a little.

GMCGreg

You must have the early style VC that had a valve built into the DS cover , haven't actually seen 1 but have heard of them . PS cover should go pre turbo, post filter ( supplies clean air into engine during non boost use ) can also vent pressure during boost , no check valve required. DS cover into catch can , out of catch can to pcv port at top of manifold with check valve to prevent boost going into can . I have another out on my can that goes pre turbo also and with some air filter restriction provides a vacuum source during boost , it also has a check valve to prevent it from being a huge vacuum leak into the pcv system. If you tee the 2 valve cover lines together you will not have a clean air in , bad air / gases out. If your can has only 2 ports I would run the PS cover hose to a remote mounted filter that can provide clean air in and vent any pressure. Maybe fender or fire wall mounted, above the height of the cover