after reading the vaccum pump post I just wanted to post this and see what you guys think of my idea, I have a procharged 93 TA I was having some blow by problems from wore rings, the motor still runs strong but I was getting a lot of pressure inside cusing some oil leaks, I cam up with a little idea and it seams to be working so far, I took 5/8 hose and ran a line from the valve covers to a jaz oil catch tank, from there where the filter should be I ran a 1 inch line down to my intake tube for the supercharger so im pulling a vaccum on the crankcase, what do you guys think of this? so far so good I havent seen any oil sence then the catch tank it gettin the extra oil before is gets sucked back into the motor, any thoughts on this? heres some pics on my site of what I had did.

jaz catch tank
http://www.streetlethal.net/pics/DSC01798.JPG
line on the valve cover the pass side has a line on it to
http://www.streetlethal.net/pics/DSC01799.JPG
line going into my intake tube right after my air filter
http://www.streetlethal.net/pics/DSC01801.JPG

 

Don't the S/C setups generally route the PCV valve back to the blower suction, to avoid pressuring the crankcase under boost? And include an oil seperator? Have you actually measured the vacuum? I would think that there wouldn't be too much vacuum at the blower inlet.... hopefully not more than a couple inches, representing pressure loss through the filter. What you are doing is allowing the high pressure in the crankcase to escape to a lower (slightly negative) pressure area. I thought this was the normal way to handle PCV on a blower setup, but I could be wrong.

 

i agree with the above post...

 

the only thing that ATI says in there book for the install is to pull the PCV and run a hose with a breather filter on it down in front of the air filter, theres no way that just that will get rid of the crankcase pressure, I had breathers on eather valve cover for a while that worked but I didnt like the fact that I was just venting the vapor into the air I could smell oil so I came up with this.

EDIT: I dont know how much vac it pulls, I had put my hand on it at idle and its not a lot but you can feel it pulling I would think at higher RPMs when the blower is pulling it would pull some decent vaccum, I might put a gage on there now that you say that just to see for my knowladge.

 

if you are still running a PCV system and its hooked up after boost thats not helping your oil consumtion any. we had this problem on a few of our mustangs w/ brand new shortblock. so it wasnt a ring seal issue....well...it is kind of. if you have to good of ring seal it causes the pcv system to pump oil in the motor. when you get a set of total seal rings, on the information packet you get with them it has an addendum about that. chucking hte pcv system altogether.

 

My PVC is ran into that tank to. that was pulled from day one accordong to ATI I had to pull it and did.

 

If it pulls any vacuum at all, your air filter is too small, or clogged.

For every 1 psi vacuum the supercharger pulls at its inlet, is 1 psi boost lost.

 

I had put a gauge on there then its nothing on the gauge, you can feel a little pull on your hand if you put you hand flat over the 1 inch hose nothing major, but nothing shows up on a vac gauge its just enough to add a little extra to help get the pressure out of the crankcase.

 

You may want to ask this question on the Forced Induction side of this forum as it has been discussed there before and other folks have done this mod too. I am sure they will be able to give you the pros and cons (if any) by doing this.

Here's a write up that was done on ProjectZ28.com:
http://www.projecttransam.com/projects7.asp

Thanks,
Claude