Oil + additive viscosity

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Billbo

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Hi guys. Just a stupid question I would like to pur out there.
I am wondering if I mix 4 liters of 5w30 full synthetic oil with 1 liter of Lucas oil stabiliser, can I find out what viscosity the outcome would be. Just putting it out there if anyone may know the calculation etc.
Regards.
Billy D...
 
I have no idea how to compute that. My issue would be that the oil stabilizer would ruin the synthetic's more consistent viscosity properties, and perhaps most or all of the positive qualities of a synthetic. And not to mention what might be the result when the 2 additive packages were mixed....

Any point in doing this? Need/want a higher viscosity synthetic, or more ZDDP from an SN rated synthetic?
 
nm9stheham said:
I have no idea how to compute that. My issue would be that the oil stabilizer would ruin the synthetic's more consistent viscosity properties, and perhaps most or all of the positive qualities of a synthetic. And not to mention what might be the result when the 2 additive packages were mixed....

Any point in doing this? Need/want a higher viscosity synthetic, or more ZDDP from an SN rated synthetic?
Click to expand...
 
Good point about ruining the syn properties. I just wsnted to thicken it up to use on my 360 but I'll just stick to good old 20w50 or maybe 15w 40 mineral oil.
Regards
Billy D...
 
xxW50 oil is usually just a bandaid for a worn or loose built engine with low oilpressure.
Lucas oil stabilizer is just a bandaid for crappy oil, usually mineral.
Why not just get a bottle of xxW50 synth. oil and use it to thicken the oil, if your engine needs it?
 
Don't use Lucas Oil Stabiliser. It dilutes the additives in your engine oil because it has very little of its own and can cause air entrainment. If you need more viscosity, use a heavier engine instead. See Lucas Oil Stabilizer.

Engines need oil flow and pressure is a characteristic of flow and viscosity. Excessively thick oil will just be relieved back to the sump without getting to the bearings. See Engine Wear.

What is the reason that you think you need a higher viscosity?
 
fjr said:
Don't use Lucas Oil Stabiliser. It dilutes the additives in your engine oil because it has very little of its own and can cause air entrainment. If you need more viscosity, use a heavier engine instead. See Lucas Oil Stabilizer.

Engines need oil flow and pressure is a characteristic of flow and viscosity. Excessively thick oil will just be relieved back to the sump without getting to the bearings. See Engine Wear.

What is the reason that you think you need a higher viscosity?
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I agree with this. If you need a better oil, buy a better oil. If you need a different grade of oil, buy the grade.

When you add any additive to any oil, you change blend that the oil designer developed.
 
Lucas oil additive sux. Tried it and it diluted my oil!! My engine is a 360 and I had tried it with 30 weight valvoline vr-1. Tried Z-max seems to have worked good surprisingly. Also tried stp and did ok. Not much out there as far as z max goes.
 
Do not use additives that worked in previous oil standards with SN OIL
WTF is "oil stabilizer" anyway I only stabilize my horses
and yes you could check how it flows at 100 degrees
but best advice is to let the oil companies do the blending
I'm using 0w-40 eruo spec in most everything- the MBENZ - BMWspec stuff except the VW Diesel which takes a low sap oil for the particulate filter (VW 507)
there are good xx-50 and xx-60 oils available but you must have the proper clerances
 
fjr said:
Don't use Lucas Oil Stabiliser. It dilutes the additives in your engine oil because it has very little of its own and can cause air entrainment. If you need more viscosity, use a heavier engine instead. See Lucas Oil Stabilizer.

Engines need oil flow and pressure is a characteristic of flow and viscosity. Excessively thick oil will just be relieved back to the sump without getting to the bearings. See Engine Wear.

What is the reason that you think you need a higher viscosity?
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The reason for a thicker viscosity is that the valve train is slightly quieter with say 20w60 as apposed to 15w40 oil. I am running an extreme energy cam with sharp rise and fall lobes and the valve train does sound a little like a solid cam profile. But I must admit the engine does feel more lively with the thinner 15w40 oil. It revs and responds better. My question is that just because the rocker gear sounds a little noisier does this mean there is potentially more stress and wear on the valve train?
Regards
Billy D...
 
Billbo said:
The reason for a thicker viscosity is that the valve train is slightly quieter with say 20w60 as apposed to 15w40 oil. I am running an extreme energy cam with sharp rise and fall lobes and the valve train does sound a little like a solid cam profile. But I must admit the engine does feel more lively with the thinner 15w40 oil. It revs and responds better. My question is that just because the rocker gear sounds a little noisier does this mean there is potentially more stress and wear on the valve train?
Regards
Billy D...
Click to expand...


Go to yellowbullet.com and get into the forums.

Click on the Uratcho race engine forum.

Click on the crankshaft thread. There are several well known Pro Stock engine builders posting in that thread about oil viscosity, bearing clearance etc.

Never use any additive in the oil. If you are using a quality oil, it was designed with everything it needs. You adding something to that oil changes the entire chemistry of the oil.

If you need to use an additive in your oil, buy a better oil.

There is zero reason to run a 20w60 oil unless you are in Africa heat. Even then it's questionable.

How are you sure the valve train makes more noise on a heavier grade oil? By ear? Not very exact.

Also, heavier oil means less flow. Less flow means less cooling by the oil. Like coolant in the engine cooling system you need oil flow.

Unless you bearing clearances are .0035 or more that oil is too damn heavy. If your clearances are that big, then I'd have to ask why.




Edit: the title of the yellowbullet thread is crankshaft size.
 
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Stress is the load (force) per unit area and strain is the deformation of the structure in response to stress. So, the stress and strain in the valve train should not vary with the grade of oil used.

I think you are more concerned with engine wear and this depends upon the lubrication regime that the engine is experiencing and this is dependent upon several factors including RPM. ZDDP in the oil creates a sacrificial wear layer that prevents wear in the Boundary Lubrication regime. However, the ZDDP layer has molecular thickness and greater concentrations of ZDDP do not increase its protection but instead extends the oil's useful lifespan. Excessive ZDDP levels (over 1400 ppm of phosphorus - the antiwear component of ZDDP) are detrimental. See Engine Wear and Engine Oil Myths.

Although a higher viscosity oil will have a thicker hydrodynamic wedge, using an oil that is too thick will cause more oil to bypass back to the sump without ever reaching the bearings and valve train.

The peppier feel of your engine with 15W-40 compared with 20W-60 means that the thicker oil is wasting power through parasitic fluid friction. The additional fluid friction of higher viscosity oils also tends to cause the oil to run hotter.

Here's a discussion about oil for old Mopar engines: BITOG: What oil for 1968 Mopar?
 
For the reasons above, the honey-like oil is likely doing more harm than good. The valve train stress will not go change overall. Listen to the valve train noise: if there are any individual 'ticking' noises, then suspect certain valve lifters of not being in very good shape. Yes, they may be new, but hydraulic lifter quality is not what it used to be.
 
67 gt said:
Billbo I don't know if your engine is a new build as I wouldn't recommend putting synthetic in unless you have some miles on it. have you tried the Penrite 15-50 ten tenths full syn ?. I use this in mine as I use the 10-30 as well solid flat tappet.
https://penriteoil.com.au/assets/pis_pdfs/10 TENTHS RACING 15W-50 (100percent PAO & ESTER).pdf
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Which oil do you use? The 15w50 or the 10w30. Also what kind of oil pressure do you get with each oil? I want to use a thinner oil but I am a bit concerned about dropping too low in pressure especially when you are cruising at about 3000 rpm and the pressure drops to about 48 - 50 psi. Also the noisier ( only sightly noisier) valve train I dont mind it if it doesnt cause problems. Have you or anyone noticed this with different viscocity oils?
 
FWIW... I have generally found synthetics to make lifter noises worse. (Been using them in various engines since the 70's..)

Keep an eye on the ZDDP levels.... the lighter weight synthetics have lowered ZDDP levels just like non-synthetics.
 
nm9stheham said:
FWIW... I have generally found synthetics to make lifter noises worse. (Been using them in various engines since the 70's..)

Keep an eye on the ZDDP levels.... the lighter weight synthetics have lowered ZDDP levels just like non-synthetics.
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Not if you buy a quality synthetic.
 
Mobil 1? And I probably ought to clarify..... it tends to happens more when cold... which would make sense with the thinner viscosity of synthetics at standard temps (30-80 F). I assume it is leakdown in the hydraulics, not impact noise.
 
Billbo said:
Which oil do you use? The 15w50 or the 10w30. Also what kind of oil pressure do you get with each oil? I want to use a thinner oil but I am a bit concerned about dropping too low in pressure especially when you are cruising at about 3000 rpm and the pressure drops to about 48 - 50 psi. Also the noisier ( only sightly noisier) valve train I dont mind it if it doesnt cause problems. Have you or anyone noticed this with different viscocity oils?
Click to expand...
Billbo I've been using the 15-50 since switching from Joe Gibbs hot rod oil about 10 k ago , oil pressure hot Idle 35 LBS , 3000rpm 60 LBS .Haven't had any issues and always check dumped oil for any shavings after pouring old oil in container for recycling and magnetic drain plug is clean. I use the new Ryco oil filters (Black type ) as they screen better than your std type but in saying that I use some earth magnets around the oil filter to catch anything just in case. Just being Anal ...
 
Billbo said:
Hi guys. Just a stupid question I would like to pur out there.
I am wondering if I mix 4 liters of 5w30 full synthetic oil with 1 liter of Lucas oil stabiliser, can I find out what viscosity the outcome would be. Just putting it out there if anyone may know the calculation etc.
Regards.
Billy D...
Click to expand...


The viscosity index will approximately be... slippery oil in the motor that won't know the difference.
Spend your time in other trains of thought.
Live long and prosper.
 
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