On page 57 of Brian Long's book you can see a nice shot of a 1977 928 at the Geneva show and see the pan peeking down. So, I guess the sway bay mountings get smashed flat and then the pan gets smacked.

 

A race car doesn't bottom as though a giant hand pushed it downward. They are always in some sort of turn. I've never seen a dip on a straight that would bottom a car.
In my car I've worn swaybar mount bolts away, scraped the exhaust, front splitter and lower bellhousing but have never had a scratch on the oil pan itself.

 

Greg I think you did a great job.
My Hats off to you man for the stealth look as well.
Definitely the way to go.

 

Kevin,
Do you know how early the deeper pans were withdrawn?

Greg, Rob,
Great work at achieving an affective solution which meet all your criteria. Very uncommon for this to happen without compromise. One might say the compromise was cost, but this wasn't a part of your criteria. Well done!

 

Yes, ok, but this isn't about race cars. It is about stock cars as they were delivered to a consumer. There does not seem to be any disagreement that the stock suspension will allow the car to bottom out when the car is driven aggressively.

 

Looking at some of the pictures in Brian's book might help someone with extensive knowledge of small differences in parts.

On page 62 there is a picture of a deeper sump identified as the stock engine. It is unclear when this photo was taken.

Edit: The fan blade on page 62 appears to be made of off-white plastic (?). On the factory floor in 1977 the fan blades appear to made of alloy.


On page 71 there are pictures of workers assembling parts. These are later shallow sump engines.

If someone reading this is close to the Porsche factory museum the exploded/disassembled engine display has a deeper sump. Perhaps it is possible to read the part number.

 

Kevin where do you get this stuff??? have you ever ridden in a 928 or driven one ?? The old very brown 1980 which is very low and runs 225x50x15 little bitty tires NEVER bottoms out the oil pan, now true I have ground off a couple tie down brackets and the heads off the bolts but the oil pan is just fine. and I have done some pretty rude things like shear off a lower ball joint and have a front wheel collapse and blowing a tire at 60 MPH or so. The pan was fine.

 

Just look at your pan. I am pretty sure a 1980 pan is the shallow version. The pan I am speaking about is about 3/4" lower to the ground.

I get this stuff by trying to look carefully at the parts related to oil control. When you do a tech inspection now on a 928 you'll really know what to look for.

 

The 78-79 cars did have a higher ride heigth look like 4x4s.....never have done a tech on a 928 almost no one runs one

 

Great work as always Greg.

At the moment I rebuild my euro s engine. These engines last here in Germany very long without problems.I think related to your findings and the little space in the heads of the two valve engines.
After changing the passage to 2/6 and building a very improved oil cooling to avoid warping valve covers these cars run as race cars flawless.

I think about my other engine and wait for your solution for the s 3.Here I have a lot carbon build up on the valves and pistons.
The rings are bad but i don´t know if all the build up comes from the bottom or over the intake?

This is a great thread and a real source for pushing our cars in the next decade.Good used engines are rare especially 4 valve here in Germany.

 

John, interjection. I spent the last few hours examining the situation yet again. If you are saying that the situation with oil ejection on your engine is the same as this stituation then you are mistaken about the oil not containing air. If you look at the picture and the video that Rob put up the oil is quite clearly very aerated and this is not simply the effect of being drawn into a transfer pump. Scavange pumps will typically mix air into oil but these images are prior to the oil entering the pump gears/rotors.

I believe a Provent, from the appearance and size, is meant to centrifuge out oil droplets from an air stream rather than centrifuge out air bubbles from an oil stream. The hydrocyclones in the dissected Honda tank were fed by pumps. Plus, applying a vacuum source to aerated oil will increase the bulk volume still further.

How much oil did you fill the sump with?


A basic volume calculation in this described system would need to include (guesstimate) 20 to 30% free air increasing the bulk volume of the oil.

 

Kevin:

While I see some critical assessments of what my research has shown, you never seem to come out and say what it takes to fix the oiling problem. Perhaps you could be specific. Are you saying that your windage tray will solve the problem? Are you saying that the oil to the heads needs to be restricted and a windage tray added? A precise statement about what it takes to solve the 928 oiling problems, from you, would be nice. By doing that, you could solidify your place in the 928 world and people could buy whatever you think will solve the problem.

I'm coming out and saying the following to everyone. This is a complex problem, with several steps required to fix it. Follow these steps and the problem with oil supply at high rpms will be fixed. Follow these steps and you won't be "pumping" oil into the intake system of your 928. Follow these steps and you won't have to think you might have solved the problem, but know that these pieces have been tested and actually do solve the problem.

That is what this thread is about.

 

Greg, I apologize -- I had not read the long, now-locked, thread from February. As I have said a number of times over the last few years I do not have the time to regularly follow the Rennlist, nor really any list. I can appreciate now why you see my remarks to be strange and maybe devious (??).

In that thread you said the issue with the 2/6 bearings is that they receive the oil last after the engine sucks air and the passage needs to refill. Yes, I remember your soaker garden hose analogy from many years ago.

This is a great theory but it does not match what happens during these rod failures. The pressure does not drop to zero requiring the passage to be refilled. As I remarked at that time -- it, the hose, is already full which simply means the 2/6 bearings receive highly aerated oil first. What does happen is that the pressure drops and any number of SAE papers explain this to be an indication of heavy aeration of the oil and why rod bearings can fail because of it. There are a number of aeration measuring devices available if you wanted to test a 928 engine to destruction while measuring the pressure in bedplate passages. You saw this on the dyno when the pressure steadily dropped.

The other thing that was heavily discussed in the closed thread was that the cavity in the first bay is to blame for many problems. Obviously I strongly agree. Also, if you want to read some more SAE papers there are many that indicate increased rpm will increase aeration. It is not controversial. Scrapers, for example, simply shift equilibrium levels.

So, really, I am not trying to steal your fire or copy your products or whatever else. You focus on one engine. That's great but there is a huge "database" out there. I really pissed off some slant six owners when I brought up technology from other engines and how it could apply. Hey, the designer of the slant six, Weertman, called it his first clean sheet engine and was proud that it used established design principles from other engines. Head-smack.

Anyways, good luck with the transfer pump. It does look like a quality item and I think it is wonderful that it will help conserve the diminishing supply of engines. When I suggest transfer pumps to racers there is usually a problem because it is considered illegal in their class. Go figure.

 

Greg, to follow up on my last post and address what you wrote here. My solution for the 928 was completely bolt in using original fasteners etc. I agonized over whether I should design parts that required people to actually drill into their parts. (I am referencing late sumps versus early sumps then the GTS.) It would be easy for me to come in and require people to drill here, weld there and on and on.

I do suggest it sometimes and I did start modifying stock parts for other more common engines. I did not do it for the 928 nor the 944 nor the 924. Wait, I did tell people they would need to relieve the inside of their pan in some cases.

I also go WAY out of my way to accommodate other manufacturers parts. Example, DCR pickups for the SRT4 with no screening. Huge public debate with him over that. I finally said that I had spoken my peace and made a baffle to accomodate it. His strap kits (and others) as well.

 

Not being combative...just making sure I'm reading what you say...you English majors can be so hard to follow, sometimes.

Are you saying that your "solution" for the 928 engine is your scraper and windage tray and this will eliminate all the oiling problems in the 928 engine?