Slightly used oil better for race engine?

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Hey guys, check out the findings in this other link:
Oil catch can

What a couple of us are noticing is that fresh oil "might" seem to aerate more than oil with say 1K of street miles. A couple of us with PCV catch cans are noticing that after an oil change is when we get the greatest amount caught. I have 3 vehicles with these and now see the same thing on all 3. For the first 500 street miles on the oil, the PCV will catch alot, for the next 4500 miles in my 3 cases, little to nothing is caught.

Combine this with the issue of ZDDP needing about 1K of street miles to fully activate. Might be a reason to look at "breaking in" the oil for the race car in the family car first if both of these hold to be true.

Let me know what you think.
 
That's very interesting. If you heat up virgin oil to at least engine operating temps in a metal cup and monitor the rate of oil lost to evaporation, you will see how the rate is highest when brand new and decreases with time. It's no small difference either. I've done these tests many times and it always happens. You should see how slowly "very aged" oil evaporates...it's amazing. I think the effect you are seeing with the catch cans filling up quickly with new oil is due to this phenomenon mostly, if not completely. Do you have any direct evidence that virgin oil tends to aerate more than aged oil? I can't rule it out but I can't rule it in either without more info. about it. On the question of aged vs virgin oil for racing, I don't know for sure. My hunch says racing with brand new oil is not ideal but I could be wrong. And if it does actually aerate more easily than aged oil, that would be bad.
 
"Do you have any direct evidence that virgin oil tends to aerate more than aged oil?"

No I don't, thats for sure. I think the way to test this is to run a test of the oil in the pan and the oil caught in the PCV catch in the first few miles to see if different. If its light ends boiling off, is the catch can enough to condense them back to what looks like a regular 30W oil.

On my truck it actually slowed significantly at the ~200 mile mark this time. The level is dead on again, but this time I am really watching everything closely. The first 18 miles were dramatically the worst also.

For racing what I was thinking was a drag only car. You will never get the oil "aged" before its dumped from fuel dilution.
 
quote:

The ZDDP also takes some time to fully activate as well, usually the first 1K miles.

ZDDP is soluble in oil and is always active and as soon as the engine turns over, it goes to work.

As far as I can tell the anti-foamant never changes in the ppm ranges since it is of a high molecular weight and doesn't evaporate.

Aged oil is never as good as new oil since chemical changes have taken place in used oil.
 
I asked Terry if I could reuse my 10 qts of $20/qt RP-41 oil with 25 1/4 mile passes, out my race car in my lawn mower generator and stuff like that. Nope not good.
I did use it to dyno an oil pump...
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I was asked for a time slip but not a comment or others. Lets's see a time slip for a owners Ricer.
 
Hey don't laugh i use my old racing 41 on my remote control car, gives me more horses
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"I asked Terry if I could reuse my 10 qts of $20/qt RP-41 oil with 25 1/4 mile passes, out my race car in my lawn mower generator and stuff like that. Nope not good."

Was Terry specific? I mean, if you could filter out the metallic particles ... with various meida, I don't see why not.

--- Bror Jace
 
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