Suggestions - oil to use for historic racing?

[Bjorn]

Hi there -
I would be interested to get some thoughts and ideeas which oil to use in my BMW 3.0 CSL - 16 valves -
I do only use the car for historic racing.
Have noticed some problems with oil pressure when using a full synthetic - so presently I use a semi-synthetic oil (Elf)
Max revs approx 8.200 rpms -
Many thks in advance for your input
Bjorn

 

[GMGuy]

What weight oil are you using and what kind of oil pressure problems? Consistant? Turns only? Left and right, left only, right only?

Alex.

 

[Bjorn]

Originally Posted By: Bjorn
Hi there -
I would be interested to get some thoughts and ideeas which oil to use in my BMW 3.0 CSL - 16 valves -
I do only use the car for historic racing.
Have noticed some problems with oil pressure when using a full synthetic - so presently I use a semi-synthetic oil (Elf)
Max revs approx 8.200 rpms -
Many thks in advance for your input
Bjorn

Correction - maybe it was too early in the morning for me : 24 valves of course - nothing else..

 

[Bjorn]

Hi Alex - Many thanks for your reply - Presently I am using Elf Competition 10W-40 ( semi-synthetic ) and have no problems - but as said above, when I used a full syn Castrol I had problems with high revs and oil pressure.

My feeling is just that I have some problems to understand why a semi-syntehtic works better than a full synthetic....
Is this ( Elf ) the best oil I can buy for money and my valuable engine ?

(Engine has a dry sump of course)

 

[Doug Hillary]

Hi Bjorn,
Castrol's Synthetic 10w-60 is an excellent lubricant for your application

Valvoline's mineral "Racing" 20w-50 is also a suitable lubricant and is used by the Porsche Factory in their historic racing engines

Regards

 

[GMGuy]

You might be running your sump low when the revs get up there, heavier oil being tougher to push through won't allow the oil pump to push so much oil through the system that the sump gets low. Hows that for a detailed technical explanation? =-)

Alex.

 

[Bjorn]

Many thanks Doug and Alex for Your inputs !
Kind regards Bjorn

 

[tdi-rick]

Originally Posted By: GMGuy
You might be running your sump low when the revs get up there, heavier oil being tougher to push through won't allow the oil pump to push so much oil through the system that the sump gets low. Hows that for a detailed technical explanation? =-)

Alex.


except that Bjorn is running a dry sump in his CSi.

 

[GMGuy]

Just saw that. =-)
The oil returns big enough?

Alex.

 

[BarkerMan]

Can you keep running the current Elf oil? It has a good rep and sounds like a good match for your situation. With that dry sump setup make sure the oil system breathes as designed and that you understand the plumbing and have it all cleaned up. This is one place that sometimes needs attention with infrequent had use.