Another question is whether anyone that has used a reground camshaft in a high performance engine has ever suffered a gear problem. After our problems with Ryan's dart I had a known good 100,000 + mile cam reground and used the original gear that matched the cam on a new pump. If the answer is no then that points to the gear/cam itself I would think. Just thinking out loud.
Not saying that aerated oil is not still part of the problem though.

Also I have seen some .528 cams sold on E-bay over the last year and it would be interesting to be able to follow these cams as they go into service. I know I will never use another one from MP unless it is used and looks good.

Rick

I had 2 opg failures over the years.
1 was street driven mild performance engine with stock oil pump and mp 276deg cam. there was a windage tray and stock pan no cam button.the engine got about 1000miles of going to work and midnight pounding on the lonely open highway. i was lucky and only had to replace cam and oil pump gear,so i up to a 284deg mp cam with cam button and only got about 500miles and same thing. i used a home made belt drive pump for many year until i read an article in a mag about doug and his solution.

After talking to seymour, he got me interrest in trying the stock setup again.doug sent me some case haedened gears but by this time i was off the street and full time racing here, i was running a full tube chassis with 11 to 1 motor, full super stock base pan, oil level was keep 6in from lowest moving parts of the crank. the cam i was using was a comp 302degs 540lift shifted at 6500rpm and over the line at 6800rpm.
the car is easy to work on so after the first weekend, about 30 pass,i checked the gears and you could see a sharp groove forming in the oil pump gear, it looked like the trailing edge of the cam gear was cutting the oil pump drive gear as it was leaving the gear face. i took the cam out used a fine stone on a die grinder and shaped the outer edges of the cam gear to the smooth shape that was on a stock cam i had in the garage, i then reversed the oil pump gear so the cam was riding on the opposite side of the gear.

After the following race weekend i took it all apart again and the pattern was like you see on a stock pump, with a smooth and shinney contact patch. so i think you need to do all the stuff that doug has proven, the oiling feed line, direct to the gear contact point, plus filing or lapping the to gear surface so they match and wouldn`t cut each other. that`s my take...

Hi Roger,

Ok, this is good. Now we can move to a deeper analysis of Baran and Chengs' results in SAE 2007-01-4109.

In the paper the percentage projected open area of the total openings on the tray versus its total projected area is given as 20%. This data is interesting with respect to the absence of the tray, of course. However, what is not listed is a percentage of open area only with respect to the section that was trimmed away and to which the mesh parameter open area refers. This is an error and creates a confound.

The image from figure 4 was blown up and traced on a monitor screen with onion skin paper. This tracing was scanned and loaded into a drawing software program and a grid imposed. Very roughly, a 38% open area was calculated for that area of the windage tray alone. Again, this is important with respect to the percentage open area of the mesh inserts used to replace it.

In figure 11 a graph is provided showing the percentage aeration versus the engine speed for five conditions. There is a consistent drop from the original condition, i.e. the original windage tray with ~38% open area to the 2x2 mesh with a 76% open area. By chance the percentage open area is about double. This relationship continues, interestingly, even at those engine rpms (6000+) which depress the 100% open area aeration rates (no tray) below that of the 2x2 mesh insert. This appears to be too consistent a relationship between two variables to be experimental uncertainty.

Why is this the case? The reason appears simple. In removing the center section of the tray a defacto large "louver" is created and thereby another experimental confound but a serendipitous one. This louver has 76% open area versus the other "louvered" area tested at 38%, i.e. the original tray. The 2x2 mesh is still open enough to allow the louver to function.

It appears that the 6x6 mesh at 62% open area also follows this relationship. Note that the weave of the 2x2 and 6x6 meshes imparts a crude non-biased crown to the wires that would act as a rough scraper.* Clearly at 14x14 this weave effect is too small and the mesh is too obstructive to allow the aerodynamic effect of the large or iterated small louvers to be at all dominant.

In the paper the selection of mesh size was arbitrary as apparently no OEM examples were known.**

The 14x14 mesh ostensibly should have been the lower end of the effect researched in the paper but by including the 2x2 and 6x6 meshes a serendipitous result emerges. The referenced** OEM selection of 17X17 and 20X20 seems to concur with the higher mesh range suggested.

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* The importance of the bias or handedness of the crown on expanded metal screening cannot be overemphasized. It acts like a cheese grater to the windage flow, stripping out oil. The bias also allows the windage flow itself to purge the louver openings of oil droplets.

** It appears that no OEM examples of wire sump "tray" screening were located. The 1960s Triumph 2000 straight six Mark 1 used approximately a 20x20 mesh over its wetsump and the mid to late 1970s Porsche 928 V8 engine initially used approximately a 17x17 mesh over its wetsump. In both cases the mesh served a dual purpose as a filtering medium for the pickup and energy dissipater. If requested, the wire diameter for these parts can be supplied.

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The seridipitously illuminated relationship shows that: when louvers are used, in order to minimize the oil aeration (distinguished from surface foaming***) of the volume of a free surface of oil beneath it, the percentage open area should be maximized. However, this principle should not be used in isolation with a dynamic system such as an engine under various lateral accelerations without careful consideration. Here is an OEM example of this principle in use (Mercedes straight six with open sump and five vertically oriented "scraper louvers" -- i.e. louvers asymptotically approaching 100% projected open area).



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*** See important results and discussion in SAE 2004-01-2913 on the same engine.

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Another issue that should be addressed regarding SAE 2007-01-4109 is that there was the tacit, albeit neutral, endorsement, deliberate or otherwise, of a .5 or 1 liter overfill since it was not shown to affect the aeration rate of a statically mounted engine from impacting oil droplets. Caveat: This is a very risky idea for modern competition engines.

A high-end Raceline aftermarket alloy sump developed for use with the 2.0 Ford Zetec engine is currently being investigated. Raceline utilizes a stock Ford windage tray and a secondary windage tray which is also a sump cover, as with the Duratec 30. When the pan is tilted at a 45 degree angle which represents a 1G lateral acceleration for a left hand sweeper in a longitudinally mounted engine **** a mere .25 liters of trapped returning oil is required before the rotating assembly begins striking pooled oil in the flooded Ford windage tray. With a 1 liter or quart overfill this amount of oil and more would automatically be present rather than depending on the delivery rate of returning oil from the engine circuits.

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**** For modern performance suspensions this is not at all extreme (the Lotus Seven replicas this pan is installed in typically pull 1.3+G laterally).

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Lastly, an additional confound is present because the same Duratec 30 engine tested in SAE 2007-01-4109 is listed as having a different amount of oil present in the pan during running versus SAE 2004-01-2913. The 2004-01-2913 paper lists 2 liters as being present in the sump whereas in the current paper 3.2 to 4.2 liters is used. Subsequent correspondance with Professor Cheng confirmed that the same engine was used in the two papers but that the 3.2 to 4.2 liter level should be used. This dramatic difference warrants further investigation.

It is suggested by myself that the engine as originally engineered by Porsche was meant to have the sump cover completely cover the reservoir oil present during running -- this allows it to also function as a secondary windage tray. The evidence for this technique from other OEM designs is overwhelming.***** In checking a Duratec engine core here the oil volume under the tray is approximately 1.5 quarts/liters. When an additional .5 quarts/liters is added this does submerge the tray and brings the level to the witness marks present in the well used pan measured: this means 2 quarts/liters total which supports the data in SAE 2004-01-2913 rather than SAE 2007-01-4109. This is also another touching of the aforementioned caveat.

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***** A good exemplar of the dual tray approach can be found in the common Toyota 4AGE engine. The lower tray that is welded to the pan interior just covers the 2 quart/liter volume present in the running engine. A second tray or "baffle" in Toyota-speak is often added to high performance versions of the motor series, such as the 4AGZE.

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As an aside, the attitude of the Duratec sump floor tray was not adjusted for the tilt imparted to the installed engine****** -- though thankfully the casting floor itself was.

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****** Whereas the attitude of the one in the high-end aftermarket Raceline sump for a Ford Zetec engine was adjusted, in addition to the casting floor.

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Remark by Kevin: I don't just make this stuff up as I go along. I suspect some people believe that.

Please see the deeper analysis of the SAE paper.

Whoa, kevin. Can you back up a little? You have lost me, and I would imagine, others. I would remind you most of the people on the site are hobiests, not engineers. We have members with all types of education, from HS drop outs to PHD's. Thanks.

_________________
Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 170 nitrous
64 Valiant Signet
64 Valiant 4dr 170
64 Valiant 4dr 225

Theories, analysis and "benchmarking" other applications is a great starting point but at the end of the day (more like, at the beginning of the race) I need to convert all that information into a working system or application for my specific engine and running conditions... in my case, a SL6 engine... on a dragstrip.

For most users here, that ends-up being the use of a scraper, a windage tray and some "baffles" welded into the oil pan.
The real value is knowing how (where) to set those items (locations & clearances) so they work well.
Do you have any info. on how to best set these items-up, in order to reduce oil aeration?
Are there any other oil return "tricks" that we should be looking at?
DD

Please look at a real slant six. Please roll it over on an engine stand. Please gather some real world data .....please formulate some ideas specific to the engine this board supports. Please test these ideas on a running, real world engine.
If possible test these theores at a sanctioned competition event. Post some 60 ft times.

Then you will be up to speed on how all this applies to a slant six.

Almost everyone here can cut and paste published information.........show me a slant sump. Show me pictures of your scraper installed in a slant sump....How about a crank scraper Tips and Tricks?

_________________
Yeah....Im the one who destroyed this rare, vintage automobile.....

Slant six oil sumps is perfectly shaped like a bathtub with sloping at the top of "sump" where oil is held, starving the oil pickup of oil. It's very easy for oil to run up the sides at high acceleration or side G forces.
As kid we used to make tidal waves and get water to crash over the edges in bath tubs. Remember that?

Cheers, Wizard

Sandy, I have designed and made more windage control devices for more different engines from more different marques than anyone else in the world. The slant six is not so unusual. Many of its elements can be found in other engines.

Kevin,

Can you post some pictures of a modified and tested SL6 pan? If not, can you post some pictures of similar oil pans that have been modified?

Will you build more SL6 crank scrappers?
If not can you post the pattern?

Thanks,

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Hi Charlie,

Wow, it has been a long time since I was over at your place. I will back it up a little.

I am going to run out and try to snag a pan.

Ted:

terrylittlejohn has posted a very good thread on sump construction including lots of pictures.

Here it is!..... http://www.slantsix.org/forum/viewtopic ... t=pan+weld

_________________
Yeah....Im the one who destroyed this rare, vintage automobile.....

Sandy,

Thanks for sharing Terry's work. A great pan design, except I don't think I can fit one like that over the K frame on my 74 Swinger.
It is pretty tight down there already......maybe a scraper since it doesn't take up much space.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

OK....Now you've taken a slightly different direction, and it gives the appearance that you're digging into the engineering with the end goal of fabricating a sump cover or set of baffles that would lend itself well to greatly reducing entrained air. I can see where the longer a lubricant in a sump can stay there without more interaction with rotating mass(es), the more air will migrate out of it.
The idea of screen or mesh integrated into a baffle or sump cover system isn't too bad, as it would give the oil a route back to the sump, but still act as a "solid" barrier to further air current interaction with the same oil. The hard part is determining just where that "line" is in the mesh count that lets it act as a barrier without keeping the oil from draining.

I would be so bold as to suggest this; While the engineering goal might be a worthy one, be careful you don't run up against a diminishing returns barrier.

If you would be so kind, do you have an end goal, and would you care to share such?

Roger