How much oil to use?

[runningmonkey]

This may seem like a silly question but am a bit confused, iv got a 3.5 ltr extended oil sump fitted to my engine (2180cc) it's also got a oil cooler and oil filter fitted to. Now iv been told not to fill the engine up to the normal fill line on the dip stick, instead fill it to the minimum line. Is this right?

[TexasTom]

That's the level I run ... same size sump & stroke.
TxT

[John Palmer]

We have always used the "bottom line" on the stick, with a deep sump system.

[Jesse/DVK]

Just touching the dipstick with my 4 qt sump

[vintagewagenwerks]

I use 1.5l deep sump system but why do not fill to the max of the dipstick ,rather i see not the reason to use a deep oil sump system.

[TexasTom]

The main reason is to try and prevent oil 'splashing' by the crankshaft. The increased stroke will allow the assembly (rods included) to reach down much further into the sumped oil and throw it about in the case, which will ultimately find it's way to the least likely places for seepage and such.
That's my take on it, in a nutshell ... 
TxT

[Bruce]

The increased stroke will allow the assembly (rods included) to reach down much further into the sumped oil and throw it about in the case,

Please explain how the crankshaft and rods "reach" down through the camshaft and lifters?

I use a 1.5 liter sump, and I fill it to the TOP line.

[John Palmer]

Please explain how the crankshaft and rods "reach" down through the camshaft and lifters?

, Trust me Bruce, "it has happened" and to us, at the last PRA Fontana race.  Oh.......one more thing "it's not cheap to repair"

[Zach Gomulka]

I use a 1.5 liter sump, and I fill it to the TOP line.

Surprised to hear that given your obsession with weight

[DWL_Puavo]

In race track use with GB 1,6ltr sump, we have to keep oil level closer the upper line to prevent starving in long fast turns. Even if the engine has windage tray (http://www.cbperformance.com/catalog.asp?ProductID=203). Engine in this case itself is 2274cc. Supposedly this could happen also with highway ramps etc or in drifting applications

[runningmonkey]

The main reason is to try and prevent oil 'splashing' by the crankshaft. The increased stroke will allow the assembly (rods included) to reach down much further into the sumped oil and throw it about in the case, which will ultimately find it's way to the least likely places for seepage and such.
That's my take on it, in a nutshell ... 
TxT

This could be the reason why iv had a few fly wheel oil seals go, Iv been filling mine 3/4 on the dip stick and had to replace the seal twice in the last 2 years!

[vintagewagenwerks]

I usse my system about 2 years never had problems and did run more than 20000km with it since i istalled it Last highway drive was over 200km with 4500 rpm .by 25 degrees outside.

[TexasTom]

The increased stroke will allow the assembly (rods included) to reach down much further into the sumped oil and throw it about in the case,

Please explain how the crankshaft and rods "reach" down through the camshaft and lifters?

I use a 1.5 liter sump, and I fill it to the TOP line.

Bruce, I guess what I was trying to say is the much larger assembly creates so much more windage inside the crankcase that things get thrown around a whole lot more. Also, the clearance to the camshaft is much tighter and splashing of the oil off the cam itself can be occuring ...
All I know is my problems were alleviated by lowering the level
TxT

[vintagewagenwerks]

so can it be that your pistonrings are damaged or your breather system is not big enough?For real when you drive without an add on sump the oil is on the same level.The add on is only to allay the oil splashing in the engine to have constant oil preasure while rough driving in curves and so on ,otherwise to have an cooling effect with his tins.

[kingsburgphil]

I use 1.5l deep sump system but why do not fill to the max of the dipstick ,rather i see not the reason to use a deep oil sump system.

One thing you may be overlooking. With a deep sump you "can" run with a lower oil level, and minimize oil foaming from high levels.

Despite the additive packages in motor oil.  IMHO 

[Fast Bug]

I use a 1.5 liter sump, and I fill it to the TOP line.

Surprised to hear that given your obsession with weight

 

[Fast Bug]

The main reason is to try and prevent oil 'splashing' by the crankshaft. The increased stroke will allow the assembly (rods included) to reach down much further into the sumped oil and throw it about in the case, which will ultimately find it's way to the least likely places for seepage and such.
That's my take on it, in a nutshell ...  
TxT

This could be the reason why iv had a few fly wheel oil seals go, Iv been filling mine 3/4 on the dip stick and had to replace the seal twice in the last 2 years!

No I don’t think so. The flywheel seal is mounted on the outside of the crankcase and is only lubed by the #1 main bearing.

By the way I fill mine to the minimum line and I have never had a problem.

[John Palmer]

With all due respect, Bruce is correct "again"!  The higher oil level and a small should work just fine on the street.

On another forum, from a distant planet, long, long ago, Muffler Mike posted series of pictures of an engine on a dyno that had been fitted with "glass viewing windows" in the valve covers.  The photos were taken at different RPM levels.  Some of the old timers around here might remember the old post.  Basically what happened was the left valve cover and head were entirely filled with oil "if I remember correctly" by only 5 or 6K RPM.  I think anything that you can do to avoid (or control) this from happening is a good thing.  We run a "very large" Berg  sump and run the oil level on the lower mark in an effort to help control the excess oil slung off the crank and rods.  Ideally there should be a better baffle covering the left push rod tubes.  A large 1 qt or over breather helps, but a dry sump system is the way to go.

[Bruce]

I use a 1.5 liter sump, and I fill it to the TOP line.

Surprised to hear that given your obsession with weight

My current car is a TANK. It's pointless to try to lighten it. 
The next car will be light!

[BeetleBug]

On another forum, from a distant planet, long, long ago, Muffler Mike posted series of pictures of an engine on a dyno that had been fitted with "glass viewing windows" in the valve covers.  The photos were taken at different RPM levels.  Some of the old timers around here might remember the old post.  Basically what happened was the left valve cover and head were entirely filled with oil "if I remember correctly" by only 5 or 6K RPM.  I think anything that you can do to avoid (or control) this from happening is a good thing.  We run a "very large" Berg  sump and run the oil level on the lower mark in an effort to help control the excess oil slung off the crank and rods.  Ideally there should be a better baffle covering the left push rod tubes.  A large 1 qt or over breather helps, but a dry sump system is the way to go.

To add to what you write above:

The Muffler Mike pictures only show the 3/4 side valve cover that is also vented. His conclusion was to remove the vent and to add a drain line to the sump. What would have been interesting was to see the same pictures with a valve cover that was not vented.

-BB-

[TexasTom]

On another forum, from a distant planet, long, long ago, Muffler Mike posted series of pictures of an engine on a dyno that had been fitted with "glass viewing windows" in the valve covers.  The photos were taken at different RPM levels.  Some of the old timers around here might remember the old post.  Basically what happened was the left valve cover and head were entirely filled with oil "if I remember correctly" by only 5 or 6K RPM.  I think anything that you can do to avoid (or control) this from happening is a good thing.  We run a "very large" Berg  sump and run the oil level on the lower mark in an effort to help control the excess oil slung off the crank and rods.  Ideally there should be a better baffle covering the left push rod tubes.  A large 1 qt or over breather helps, but a dry sump system is the way to go.

To add to what you write above:

The Muffler Mike pictures only show the 3/4 side valve cover that is also vented. His conclusion was to remove the vent and to add a drain line to the sump. What would have been interesting was to see the same pictures with a valve cover that was not vented.

-BB-

With a stock oiling system, the 3/4 side is the only side that will fill! I believe it's due to the direction of rotation of the crankshaft, much the reason many V8 engines are only vented on one side?
The reason I specified 'stock oiling system' is a case with the 'Bob Hoover oiling mods' will flow more oil to the 1/2 side and potentially fill that valve cover more than without, though I have no scientific proof ...
It would be interesting to devise an internal baffle of sorts for the left-side of the engine only to shield the returning oil and see what improvement could be made, versus return lines from the head to the sump. Though, you would think it had been tried by now already.
TxT