How much oil to run in an inverted Porsche 930?

[Dimi Terleckyj]

Hi Ron

Be guided by how high the level is in the standard orientation compared to the shafts and gears.

If the standard level only submerges one shaft then only one shaft should be submerged in the inverted orientation.

Bear in mind, the level on the crown and pinion gears, as well in both orientations has to be a consideration.

Dimi

 

[Ian Anderson]

Would Porsche themselves not have this information?

I am sure thay are aware their boxes are used/ reused / abused in other applications and could probably assist

Just a thought

Ian

 

[flatchat(Chris)]

Aaah-- 4 Litres = almost 4 Kilograms (~2Lbs )
5 Litres = approx 5 Klgs ---etc = too much weight
go back to 4 Litres :!blank:

 

[Ron Earp]

One picture worth a lot of words:

 

[Ian K]

Ron,

Which companies have you already contacted? I assume Renegade and Kennedy, but who else. I am in San Diego, and there are a lot of local shops here that play with Porsche boxes.

Ian

 

[Ron Earp]

Ron,

Which companies have you already contacted? I assume Renegade and Kennedy, but who else. I am in San Diego, and there are a lot of local shops here that play with Porsche boxes.

Renegade, Kennedy, Gbox, California Motorsports.

 

[Terry Oxandale]

Is there any differences in lubricating requirements for the bearings or friction surfaces between the two shafts? Just because one shaft was emersed, is that characteristic of the oil level transferable to the other shaft without causing oiling issues with the originally emersed shaft?

 

[Jack]

I have been told (same sources as Ox) that 4 quarts is sufficient. Consideration for pump/cooler/filter/hoses not withstanding. The locations of these additional components may come to bear as well (cooler & big filter above gearbox level) unless constantly running the pump. Or am I overthinking this?

 

[Ron Earp]

I have been told (same sources as Ox) that 4 quarts is sufficient. Consideration for pump/cooler/filter/hoses not withstanding. The locations of these additional components may come to bear as well (cooler & big filter above gearbox level) unless constantly running the pump. Or am I overthinking this?

I'm probably over thinking it too but I will do the experiment and photo the results.

The cooler is easily measured and won't hold that much. Ditto the lines, know the ID/length, simple calculation. Pump volume is pretty easy too.

Maybe 4 qts will come out on the money.

 

[Jack]

Ron,
I will be using a big Peterson 400 series filter. That thing may hold nearly a quart, I'll measure it.

 

[Jack]

Okak Ron, here we go..filled my cooler & filter with oil, same for hoses. Poured into wife's measuring cups & did the conversion to quarts.

Peterson 400 filter = 0.37 quarts, test
SETRAB oil cooler (51-07944) = 0.41 quarts, test
Pump & hoses (AN-8) 0.612 quarts, calculated + test

Total 1.39 quarts plus the gearbox at 4.0 quarts gives us 5.39 quarts total.
This seems just a bit high to me so I'll go with 5 quarts initially.

And yes, I cleaned the measuring cups..

 

[Ron Earp]

Total 1.39 quarts plus the gearbox at 4.0 quarts gives us 5.39 quarts total.
This seems just a bit high to me so I'll go with 5 quarts initially.

.

But do you know the gearbox is "properly filled" at 4 qts? That is my initial question.

I've had answers all over the board for this query- 4 qts, 3 qts, 8 qts!!!!, 5 qts, and these answers were not counting coolers, lines, pumps, and filters. So, when I got this many answers from all sorts of respected sources clearly I knew something was amiss.

 

[Jack]

I've been told all along that 4 quarts was okay so it wasn't questioned. Now I'm wondering too.. Think 3 qts is insufficient, definitely not 8 qts. So, 4 or 5 has to be the number?????????????????????????????????????????????????????????????????????

I'm confused too........

 

[Ian K]

I got a reply back from Patrick Motorsports. They say 3.4 qts not including cooler and filter. I specifically asked about running it inverted, and can ask for verification.

Ian

 

[Ron Earp]

I got a reply back from Patrick Motorsports. They say 3.4 qts not including cooler and filter. I specifically asked about running it inverted, and can ask for verification.

Ian

And then try California, Gbox, and Renegade - all gave me different numbers and I had other people call too, who also got different numbers on the same day! The 8 qt number came from some Porsche racing outfit in the Northeast.

We know eight is too much.

Three seems too little.

I'm out to the garage to measure it up.

 

[Ron Earp]

Okay, here are some pictures with my measuring setup. I kept the drain hose from the bottom of the transaxle to my cooler on the transaxle. Then, I added a clear hose that is approximately as long as the hose from my cooler/pump back to the transaxle. So, in theory this setup takes in account the fluid in the hoses.

Here is what it looks like with four quarts of oil in the box. Not sure I'd want to put any more. What do you guys think? Important parts submerged? I'd estimate the oil level is to the bottom of the stub axle seal in the side plate.

 

[Jack]

Here is what it looks like with four quarts of oil in the box. Not sure I'd want to put any more. What do you guys think? Important parts submerged?[/QUOTE]

Thanks Ron, method looks good. Still need your questions answered.

Anyone, anyone??

 

[Ron Earp]

If you look at this old picture of Russ's then it appears that we might just be getting to the level of the pinon gear almost. Not quite, but very close. Since we're running the ring in a full oil bath oil has got to be flying all over the place in the diff housing area, so I think we'd be good with four quarts. My pump return comes in this side of the box, back in the gear area, at about the level of his spray bar. Since the lower shaft is definitely running in oil I'd think we'd be fine for lubrication back there too, but then again, I might be wrong.

Ron

 

[Terry Oxandale]

If you look at this old picture of Russ's then it appears that we might just be getting to the level of the pinon gear almost. Not quite, but very close. Since we're running the ring in a full oil bath oil has got to be flying all over the place in the diff housing area, so I think we'd be good with four quarts. My pump return comes in this side of the box, back in the gear area, at about the level of his spray bar. Since the lower shaft is definitely running in oil I'd think we'd be fine for lubrication back there too, but then again, I might be wrong.

Ron

In the photo above, which shaft of gears has the gears firmly locked in place, and which one allows the gears to rotate on bushings (assuming typical transmission construction)? If the lower shaft is the fixed or solid piece (with gears cut into a solid shaft), would the importance of it now being submerged in oil be as important as the upper shaft gears floating on bushings, which is now in the "dry"? On the T-5 trannys that I've built, this was the case with the counter gear in the oil, and the mainshaft (with floating gears) that drove the output shaft was in the "dry".

 

[Ron Earp]

If the lower shaft is the fixed or solid piece (with gears cut into a solid shaft), would the importance of it now being submerged in oil be as important as the upper shaft gears floating on bushings, which is now in the "dry"?

I have no idea. I don't know transaxles well and what little I know, I know least about the 930.