Author Topic: Crankcase EVAC question (Read 311 times)

68EFIvert · « **on:** June, 08, 2010, 11:36:50 AM »

After talking with a twin turbo guy at a show this weekend I decided to look further into adding a crankcase evac system on my car. It basically takes the excess pressure from the crankcase and sends it down to the exhaust system. I hear some great things about them but it look like some of the benefits to a street car are not as big since we run mufflers that restrict the exhaust. My engine has a blower of course which can magnify the crank pressure problem. The only vent I have goes from the breather in the valve cover and connects via 6an (3/8") tube to the blower inlet shield which covers my filter. I also have a PCV from a turbo T-bird.

I have a couple questions for you guys. Do you attach the nipple on the exhaust pipe before or after the oxygen sensors? So you still run a PCV valve when you use a crankcase evacuation system?

I don't like the look of the aftermarket kits from Moroso becasue they look like 1960's breathers. Doesn't fit with the look of my engine compartment. I plan on going over to NAPA and getting some gromets and 90 degree 1/2" fittings for the valve covers. For the tube that goes into the exhaust I will use 1/2" pipe. I assume that I would want about a 45* angle for the tube to the exhaust? Connect the two with some hose and I am done. I am not missing any other parts am I? I can't see why they would need a check valve but I thought I should ask.

M66Stang · « **Reply #1 on:** June, 10, 2010, 09:16:12 AM »

I used the Moroso kit on some crappy valve covers to try out a crankcase evac on my engine. I agree that they look crapppy. Was thinking of using some -10 AN bulkhead fittings and the Summit twist-tite hose on my real valve covers. I will have to make a baffle of some sort though.

You definitely want the pipe nipples down stream of the O2 bungs or you will foul the sensors.

The nipples should be installed at 45 degrees to the pipe and I think the check valves are a good idea.

Thanks,

Mark

silverblueBP · « **Reply #2 on:** June, 10, 2010, 09:39:45 AM »

I've been running that same setup for 2 years, got rid of the oil blowing out of the breathers in the valve cover.

I have the caps in the VC's with braided hose running down to the headers.

68EFIvert · « **Reply #3 on:** June, 10, 2010, 10:02:52 AM »

I am well on my way on this project now. I purchased a couple check valves from NAPA ($20 each), two grommets for the valve cover ($4), two plastic 90 degree elbows ($12) instead of breathers, 4" 12" npt pipe from Lowes ($1) and I already have 10 AN hose from running my heater hose. I'll weld the bungs in after the O2 sensors as you suggested. It should look really clean and more importantly stop some annoying leaks before they start or get worse. I'll post some pictures when I have time to take the pictures. Thanks for the help guys!