Fabio421

So, what is the concensus here? I am still battling oil control issues on my turbo car. I have one of Carl's baffles inder the oil fill/catch can but I am still blowing oil out of the cans vent ( I have it vented to atmosphere with a filter) when under boost. As for the oil return that goes into the top of the oil pan up front, I modified it per another listers reccomendation. I chopped the bottom part of the tube off flush with the pan. Was that a no no? Help!!!!

Whats so different about the provent VS other air/oil seperators? I see that DR is selling his provent kit for $375. but there are plenty of air/oil seperators for sale in Jegs or Summit for between $45 and $75. What is so great about the provent? And what is in this kit to justify the $250 above market price?

Z

Yes.

Fabio421

Thanks Mike. Why?

Z

The tube extends down into the oil pan below the level of the oil. It acts like a "trap" filled with water on a sink that prevents sewage gasses from going up and out the sink and into the room. Cutting the tube off so that it's open end is now above the oil level in the pan does away with that "trap" effect. Blowby in the crankcase can now travel up that tube. When it does, it will carry oil that's trying to run down the tube back up it instead. Put a section of clear hose there instead of the tube and you'll see oil running downwards at times when there's no or little blowby. Watch the tube when the engine's at higher speed/load and has more blowby, and you'll see the oil change direction and creep upwards along the walls of the hoses.

toofast928

All boosted engines have increased crankcase blow-by. The idea is to have the crankcase so well vented that pressure can not build.

It takes .5 psi for the sump oil to be pushed up the submerged oil drain tube, and flood the oil separator.

By cutting the oil drain tube flush with the oil pan two things happen: Oil has no way of going up the tube, and the tube becomes another source of crankcase vent.
My set up for the past year consists of Carl's baffle, cut drain tube, use 7.5 qts of oil, 20-50W, and a Moroso catch can after the Porsche oil separator. The result: Few drops of oil to drain every 3000 miles!

NoVector

Do you have any blow-by with your car? It seems like I remember you saying you were having some block pressure issues or blow-by with one of your cars (but I think it was your 84?)

I have one of Carl's kits on my NA 84 and it blows oil BAD out the elbow on the valve cover. Even with a check-valve, it forces the oil up past the check-valve and out the hose... I'm sure it's my blow-by/engine pressure that's causing it on mine.

Bill Ball

For a 5L engine, the amount of blowby that needs to be ventilated is substantial. Roughly 75L per minute at 6000 RPM (using 0.5% blowby rate).
http://www.106rallye.co.uk/members/d...hersystems.pdf

Vilhuer

Late MY pans do not have hole for return/fillup line of the early MY cars made into pan but casting has place ready for it. At least GTS pans don't have it but since place is there its logical position to put return line. Will old style tube clear aux belts or is '86 MY tube needed and why '86 MY tube has different part number?

AO

FYI... On my oil return from the provent, there is a check valve to prevent backflow when under boost. As soon as I see vacuum, the oil is allowed to drain back to the pan via the dip stick tube.

DR

For 85-88 32V engines you can drill and tap the stock oil pan block-off plate, and install a 1/2" fitting. Unfortunately Porsche wants $30 for that stupid plate so we make our own out of 6061 aluminum. A ProVent check valve is integrated in the hose assembly. (see pics below)

As mentioned, for 89 and later there is no block-off plate. So modifing a new $50 (grrrr) dipstick tube was the way we decided to go to make it an easier install (pic below). Of course, if you happen to have your 89-up oil pan off for some reason, drilling and taping it for a 1/2" fitting is a better option.

Fabio421

This is the car. It had a stuck ring in the #7 cyl. ( from what I can tell) when I bought it. After a few treatments of marvel mystery oil in the cyl. (through the plug hole) it showed marked improvement. I haven't done a leakdown test lately but the leakage had decresed by more than half in that cyl. the last time I checked.

toofast928

Very cool Dave

DR

Thanks, those are the easy ones.

For the 32V engines you need a 4-way cross fitting with a 60 degree angle on one port for the cam cover connection. I am picky and want the hose connectiions to flow with the shape of the motor and not bind up the hoses(see pics). Don't find that stufff in catalogs, so we have to make them here.

Glen McCartney

Sweet Dave, can't wait to get the pieces and finish these projects!