Redline 10w60 or LiqiMoly?

[G80indy]

Originally Posted by 94jedi

Thanks for all the input guys, thinking of picking up 3 qts of their 5w40 to thin it out, as suggested. 6:3 10w60:5w40 seem ok? It gets hot here in NC and under spirited driving I'd like to have that piece of mind.

That averages out to 5.33 HTHS (fresh oil)

[kyrix1st]

Originally Posted by 330indy

That averages out to 5.33 HTHS (fresh oil)

I have questions with "blending" oils of different viscosity.

I blended Redline 10w60 and 0w40 (7:2) this time. Prior to this, I used BMW TPT 10w60 which saw ~1L consumption in 1500km.

So far my oil consumption is reduced to ~400ml per 3,000km including two track days, one at Okayama international (30 full out laps with some traffic). You can see that oil consumption is noticeably reduced, all conditions except oil filler cap (changed to E46 M3) stayed equal.

My questions are:

1. I would have to say oil viscosity is proportional to oil consumption in our engines. Would it be the case that fluid of 0w40 kinematic viscosity inside the total fluid is the main culprit in oil consumption?

2. I would have to assume oil viscosity of 0w40 and 10w60 achieve their grades with different properties. Does averaging kinematic viscosity work with evenly blending oil properties?

[dparm]

Originally Posted by kyrix1st

I have questions with "blending" oils of different viscosity.

I blended Redline 10w60 and 0w40 (7:2) this time. Prior to this, I used BMW TPT 10w60 which saw ~1L consumption in 1500km.

So far my oil consumption is reduced to ~400ml per 3,000km including two track days, one at Okayama international (30 full out laps with some traffic). You can see that oil consumption is noticeably reduced, all conditions except oil filler cap (changed to E46 M3) stayed equal.

My questions are:

1. I would have to say oil viscosity is proportional to oil consumption in our engines. Would it be the case that fluid of 0w40 kinematic viscosity inside the total fluid is the main culprit in oil consumption?

2. I would have to assume oil viscosity of 0w40 and 10w60 achieve their grades with different properties. Does averaging kinematic viscosity work with evenly blending oil properties?

A thicker oil alone may not be the primary reason for reduced consumption. It is a big part of it, but not all of it. Red Line and the BMW/Shell oil have very different chemistries and additive packages. Every engine and driver are different so sometimes you need to experiment to see what works best. If you've found a combination that can maintain oil pressure while reducing consumption, then stick with it -- but that exact blend may yield different results for another owner.

You can estimate the new viscosity with simple algebra, yes, but that's not going to be perfect due to standard manufacturing variances. The spec sheets are just showing you the approximate viscosity/specs, not the actual. Send in a sample of brand new oil to be tested -- it will not match the spec sheet exactly. I have seen viscosities off by as much as 10% and additives off by just as much.

[Dakar Bam]

I only use 10w 60 liqui moly or motul 10w 60. While pressing the car hard it very seldom moves over the half way mark. Under normal driving in power mode the temps is at 3/4