Best spot to pull vacuum on ls2 nitrous motor

Valley would be The spot for the least oil.

Collinsautomotive said:

Valley would be The spot for the least oil.

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disagree...had the best luck from the front of the valve cover. Several years ago, tried pulling from valley with a baffle and would suck tons of oil. just moving to valve cover solved it.

Nutcase said:

disagree...had the best luck from the front of the valve cover. Several years ago, tried pulling from valley with a baffle and would suck tons of oil. just moving to valve cover solved it.

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That's what I am hearing mixed reviews. Anybody else?

Ours is in the valley cover, we built our own baffle/shield on the under side and will get maybe a few drops.... check it every 3 passes.

ATVracer said:

Ours is in the valley cover, we built our own baffle/shield on the under side and will get maybe a few drops.... check it every 3 passes.

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Got any pics ?^^^ from the underside?

No, sorry.
it pretty much looks like a small cup thats cut in 1/2 and weled to the underside. You want the fitting for the vaccum pump as far back into the "cup" as you can.
Hope that made sense.

ATVracer said:

No, sorry.
it pretty much looks like a small cup thats cut in 1/2 and weled to the underside. You want the fitting for the vaccum pump as far back into the "cup" as you can.
Hope that made sense.

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I got it , I have the Star Machine fitting and baffles so that could work

Opening faces the back of the motor also.

I tried mine in the valley and it sucked tons of oil. It would blow shit all over the engine bay. Moved it to the valve cover and it works perfect.

I used two baffles, the moroso fitting and I bolted a 6" peice of c channel to the valley cover and welded up the end by the cam gear. Still would fill the breather tank after 3 passes.

If your sucking oil out of the valley, you got oil drainback problems.

On this and our last motor we had it in the valey. like wayne said it looks like a tube pointed to the back but slanted down just a bit. then it has to make a 90* turn up. also a baffle on the first section with a drain back hole. we get very little oil in the catch. the opening is probably dead center of the motor(front to back) and the fitting is near the front of the valey. if you put the fitting in front with no baffle i would imagine the cam will throw the oil thru that window toward the fitting. ours is over a "closed" section where i don't think there could be much splash.

Maybe also do some testing to see if you pull the car up start it in the box and make a pass does it not suck oil verses idleing it up and makeing a pass. if so its more than likely drain back/slinging the drainback all over the valley area.

Are the guys with drain back oil problems aluminum gm blocks?

Ours is in the valley as well. We put it at the very front of the valley cover with a home-made baffle. We also welded in an extension off the valley cover to help prevent slosh back at the big end of the track from being sucked out by the pump. Ours has been excellent so far.

Any pictures of the valleys?

I run mine off the pass side valve cover with no problems.

I have a dailey belt driven oil pump with scavenge and it sucked oil when tied to valley. C5R block. Changed to front of valve cover and good to go.