Originally Posted by BC

Bill - I feel like you may have.... an incomplete picture. I also feel as though I need more info to see where you are coming from on this.

I drive my 928s every day (when I have them, when they are together, when I am not in danger of being arrested if I drive it, etc) - and I go through ALOT of oil. As in maybe a quart or so every week or two. Sometimes less, of course, but if I am driving to OC or LA from SD, I usually see about a quart of loss or more over about 300 miles or so. This is from the extended high RPMs from 80-120mph which is what I do on the longer jaunts. Its not leaking out the bottom. Its not in any catch cans ( I don't have any) - its being burned.

Some is going past the rings probably. Some is going past the valve seals. But most of it is simply being pushed (or pulled) into the intake and simply burned.

Not good.

If you are burning a quart of oil through the valve seals in 1000 miles, you would be smoke screening the neighborhood on deceleration (more vac in the ports).

I'm confused about your oil usage. Is your car an automatic?

I described how I see the death spiral in my other longer post. Did you see that one?

Originally Posted by Bill Ball

I'm not burning a quart in 1000 miles. Dr. Bob is or close to it now. Funny how that breather system starts throwing quarts of oil into the intake as the car gets older. I'm thinking of putting a scavenge pump in my intake. Actually I rarely add any oil between oil changes unless I ORR the car. I think that's more the case than not with S4s. Yes, it's an automatic ???? Doesn't mean I drive it like an old lady (see burnout video - and that's NOT an OIL cloud!!)

Death spiral? Sorry, not interested in learning more about death today.

Originally Posted by Bill Ball

Dr. Bob, you need to borrow your wife's turkey baster and scavenge out that intake oil. I've devised a turkey baster based scavenge system and will undercut Greg's price by $1000. I don't need you-know-who to copy Greg's handiwork. Mount the turkey basters in the cam cover breathers. Leave the hood off. Every 500 feet pull over, rev the engine to 6500 RPM and squeeze a turkey baster, remove the oil filler cap and and drop the scavenged oil in. Repeat. Problem solved!

OK, sorry, I'm done messing up this thread. Rob, I hope you never burn another drop of oil while Dr. Bob continues to pollute all of LA with his smoker because I told him he didn't need a fancy scavenge system.

Brendan, if you didn't offend me, I accept you apology in advance.

Originally Posted by Bill Ball

As to the oil pool in the bottom of the intake - Of course, I have seen that and of course it would be better if it were not there. But it's not a huge amount of oil. Like I said, unless I ORR at Autobahn+ speeds, I don't have any significant oil loss over a year period of otherwise very hard driving. Yes, there will be a pool in the intake, but if my oil loss is measured in ounces or even a quart or so over a year of driving, this is just not a significant problem. Now, it appears GTS's and some others have more oil loss, maybe from the breather, maybe from poor oil control rings. I suggest Dr. Bob might have other reasons as well, like valve stem seals, which I think have finally worn in my car. Anyway, to handle the small oil loss I have through the breathers I don't think requires a complex scavenge system. It's just not much oil over a year. If some cars burn a quart in a 500-1000 street miles, they've got problems probably in other ways. Maybe the strokers, like Rob's and Andy's are different and you have the answer. But please don't suggest Dr. Bob needs to have a $4000+ scavenge system put on his S4 that is burning some oil now. It would be best to rule out other more likely causes of oil burning. I agree. Look...I'm not like you-know-who. I'm not going to ever sell something that isn't appropriate for the application it is being sold for. I'm not suggesting that Dr. Bob needs a wet sump pumping system to keep from burning the amount of oil he does...that would be absurd. I'm just saying that the oil in the intake system comes from the heads and the harder he would drive it, the more oil would be pushed into the intake, because the heads fill with oil. Although I've not tried one, I suspect that DR's Provent System would eliminate most of the oil in the intake system on most street driven vehicles....and return it to the crankcase.

I understand Rob and now Andy do not have shrouds. I was assuming the pickup tubes for the scavenge system replaced them. There are both breathers and pick-up tubes, in there. The two had to be carefully designed to work together and do their jobs. The pick-up tubes are not "in the oil return" passages. I did not want to restrict these passages. If the pickup tubes do not go far down into the head, then are you saying that the heads fill completely with oil up to the roof? No. The engine would run out of oil long before this could occur. Wow! Never seen that on my car. And even though George seems to think he's now packing oil in his heads (you've got everyone worried!), There is no doubt he is...as is everyone that is running these engines at high rpm for long periods of time. I've watched his little cam vent screens over many, many test sessions and they looked dry enough to me, maybe a little misty - and he has shrouds on all breathers! A couple of years ago when his engine was sick with 12+% leakdown it did blow oil out these vents and create a smoke cloud when we did some speed runs. It doesn't do that anymore so I'm not sure why George brought that up. George, what's up with that?

Anyway, I don't want to drag this out. I only entered the discussion after I interpreted dr. Bob's comments as implying he might need this to cut down on his S4's oil consumption. Oil consumption in S4 street cars has never been a big issue to my knowledge and my experience. If it is, I think about valve stem seals, etc., before I would suspect that the intake would account for a quart in a 1000 miles of street driving, even aggressive LA style.

Signing out on the subject, I hope.

Originally Posted by blown 87

My engine, with less than 30,000 miles since a full rebuild uses at least a QT every 1,000 miles.

Originally Posted by Bill Ball

Hi Rob: Thanks for answering. The reason I'm not fully accepting that there is much benefit to this scavenge system even in Andy's car is that I think we do not know the level of oil packing, it's real effects, and what is influencing it. Greg made numerous changes to the engine before he dyno'd it and saw the ejection. I don't know if this would happen with, say, a more "stock" stroker. For example, when we were installing the IJ scraper and windage kit in Dennis's current motor, I liked that the shrouds on the oil drain paths from the heads kept the oil away from the crank and slung oil from going up the drains. That seemed like a good idea. But the more I looked at it, the less I liked it because these shrouds were boxed in and they went down into boxed-in conduits that lead down the sides of the pan into the sump. My concern was these boxes were going to restrict head drainage, so we eliminated most of the lower conduits and opened up the shrouds a bit.

Originally Posted by Bill Ball

... So, why do it? People think these shrouds must reduce oil in the breathers, but do they?

Originally Posted by Bill Ball

Kevin: Thanks for the comments about your drain shrouds in the message 2 up from this one. In the quote in your message immediately above I was not talking about your drain shrouds. Instead I was asking questions about some breather extension tubes Porsche put on 1 of the 2 breathers inside each cam covers. Greg installed two more in Andy's motor I guess thinking if 2 are good then ones on all 4 breathers must be better. Instead this created an unexpected oil seal of the breathers such that oil shot out the breather outlets at sustained high RPM and this initiated the development of the subject oil scavenge system.