JRracing

iTrader: (35)

When is it time to get a vacume pump? When it starts burning oil, forcing it past the rings? As I of right now, I'm not sure how I'm going to vent the motor.

I thought about welding a -6 or -8 AN fitting to my valley cover. Then could I rund a line to one of the heades? Like a syphon deal.

LS1-450

iTrader: (33)

Are you saying that you are running an un-vented motor? Only time I would use a vacuum pump is if the lack of vacuum was causing major brake issues.

Easy way to vent the motor, is to get an LS6 valley cover, run a line from the valley cover to a vented catch can. Install a PCV valve in the line that opens (allows flow) to the can. Then just use breathers in the valve covers & you're done. Just don't run the LS6 line to the intake if you use valve cover breathers. Make sure it goes to a vented can.

JRracing

iTrader: (35)

The car has manual brakes.

I wonder if a breather in the valve cover would cut it or do I need a pump pulling a vacume on the motor to help vent it properly?

LS1-450

iTrader: (33)

You don't need a pump. Air will travel in the valve cover breathers, down the push rod clearance holes, into the crank case & out the LS6 valley cover nipple or a nipple that you add to your valley cover. Then the air will flow out the nipple, through the PCV valve you add & into the vented can. This is the easiest & cleanest way.

Other option, run a stock like PCV set up where both valve covers are connected to a single PCV valve line that runs into the intake or can connect @ the throttle body. The vacuum from the intake will suck air & oil from the valve covers & into the intake. The PCV is positioned to open toward the intake. Could also run the line to a catch can on the way to the intake.

Chhh Chhh

iTrader: (2)

trex or bigger jk a huge *** cam

Jason 98 TA

iTrader: (4)

We haven't seen much gains from vac. pumps on the ls engine. My Z06 made 3rwhp with the vac pump installed Not the best hp for $700!!

99blancoSS

iTrader: (115)

Are you talking about a dry sump?

As far as venting your engine there are different ways to do it but if your routing it back into the intake you want a catch can setup.

I think your confused a little about things or terms.

You can vent from the valley pan and use the pcv and a catch can or you can plug that off and vent from the valve cover, you can vent to a catch can or direct to atmosphere or both.

You have many options. What valve covers are you going to run? Need to know more about your setup.

JRracing

iTrader: (35)

I will be using the GMPP Chevrolet valve covers. And my valley cover is a thick sheet of aluminum with a bow tie engraved into it, it made very well. And the intake is a vic jr. So I want a very clean looking set up that works well. I'm not sure when one needs it on a motor. I will be spraying this motor with a small shot after the first season. 250 max. I thought something like that might require a vac pump due to the pressure it puts on a motor.

I don't want to buy if it is not needed.

Like Jason said, 3hp for 700 bucks is not worth it.

I like the LS6 style pvc setup. Maybe I can do something like that. Weld a -6 or -8 male 45 in the rear of the valley cover, then run the hose to a catch can with a breather. Would that work?

What do you guys know about the pumps off of a trailblazer or something like that? A buddy of mine was telling me about it.

99blancoSS

iTrader: (115)

I would suggest checking out a few pcv setups.
Also your confused on what an external vacuum pump does and its use.

You would be better to vent each valve cover to a catch can.
Nasty Performance has a nice atch can set as well as RevXtreme and I offer them both.

You could also run a vented oil cap with a filter on it.

As far as charging the crank case due to using n2o it should not happen. That's what the rings are for.

Chris@Straightline

iTrader: (1)

also, if you arent careful and pull to much vacuum on the motor you'll actually start to pull oil off of necessary surfaces and trash the motor.

LS1-450

iTrader: (33)

Yes, but, you must also install a breather in each valve cover. This allows air to enter each valve cover, travel down the push rod openings, into the crank case & out the valley cover. As we discussed earlier, install a PCV valve between the valley cover & catch can w/ the PCV valve opening toward the can.

However, if your install is seasonal (fresh motor each season), then it's not as important to vent the crank case through the valley cover. Venting the valve covers alone is sufficient enough to keep from blowing seals. If your install is longer than seasonal, then include the valley cover through PCV to can.

There's a great thread on this site titled "understanding PCV systems," by 4096__. It's a good read & may be helpful.

JPH

iTrader: (2)

Yeah, the wrist pins taking the hardest hit. Don't put a vaccum pump on your motor JR, drag/race motors that have vaccum pumps on them are usually built around them, like ring packages, wrist pins, seals, certain oil pans, etc.... Put your money towards a breather/bung in each valve cover and run them both into one tank.

JRracing

iTrader: (35)

OK so the vac pump idea is out, sounds like I don't need one.

The simple idea sounds like a breather in each valve cover. I could buy two right sides that have the oil fill hole and run a large breather in both. The left valve cover just has the small hole at the rear.

A catch can and hoses is just more stuff to work around or deal with. I'm trying to keep this as clean as possible. This is a total drag set up. So I'm not really worried about a catch can unless needed.

JRracing

iTrader: (35)

Here is kinda what I had in mind. But running the valley tube out of the rear for a cleaner look.

But would I have to run a hose out of the catch can to the vic jr intake?


https://ls1tech.com/forums/showthrea...ht=systems+pvc

TLewis4095

iTrader: (10)

That setup in the pics is just a vented overflow can so you would have a serious vacume leak if you ran a line to the Vic Jr, If just venting excess pressue than the 2 breathers will do that. You will need to change oil after every race to avoid engine damage from the corrosive byproducts left in the crank-case. Good practice anyway.

JRracing

iTrader: (35)

So I could just buy two right side GMPP valve covers with the fill hole, and run a big breather is both? This would be simple.