# Will a 20wt Oil have the same protection as a 30wt?

Who wants popcorn?
With real butter!

If you are trying to prevent your daughter from getting knocked up keeping her boyfriend one room away is just as effective as keeping him two rooms away. But for some reason, I sleep better at night knowing he is at least two rooms away.
LOL, not sure about that. False sense of security right there, which is about right when making this general comparison of oil weights. I'd have easily found my way in there even if kept in the house next door.

I'm just curious now. It may have been discussed on bitog and i have forgotten ...

Q:
Technically speaking, what's the highest HTHS that can be formulated today within a given viscosity grade?

For example a 20 has a limited KV band (SAE Spec) and at some point, I assume you will hit a HTHS ceiling no matter what. Ideally speaking and with the current knowledge and technology, is there a formula that can calculate that (max attainable hths)? Let's say SAE x, API y, Standard or optimum add pack.

Not trying to invent high heel hiking shoes but curious how far you can push that limit with today's science and technology.

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Not a thick vs thin debate, just a simple question.

I have seen a number of XW-30 oils with an HT/HS of around 3.0, +/1 a tenth or two percent. Red Line, and I am told others, has a 5W-20 oil with an HT/HS of 3.0. Will a 20wt with that number offer the same protection as a 30wt with a similar HT/HS?
There is not much difference between an XW-20 and an ILSAC XW-30. An XW-40 is quite a bit thicker though. Moreover, ACEA C3 XW-30 oils are more like XW-40 oils, being a lot thicker than ILSAC XW-30 oils.

I'm just curious now. It may have been discussed on bitog and i have forgotten ...

Q:
Technically speaking, what's the highest HTHS that can be formulated today within a given viscosity grade?

For example a 20 has a limited KV band (SAE Spec) and at some point, I assume you will hit a HTHS ceiling no matter what. Ideally speaking and with the current knowledge and technology, is there a formula that can calculate that (max attainable hths)? Let's say SAE x, API y, Standard or optimum add pack.

Not trying to invent high heel hiking shoes but curious how far you can push that limit with today's science and technology.
For an XW-20, the theoretical HTHS maximum is roughly 3.0 cP if you play with my HTFS/VII calculator and keep the base-oil VI under 150.

If you are trying to prevent your daughter from getting knocked up keeping her boyfriend one room away is just as effective as keeping him two rooms away. But for some reason, I sleep better at night knowing he is at least two rooms away.

In such an instance I prefer 20 gauge to 20 grade.

For an XW-20, the theoretical HTHS maximum is roughly 3.0 cP if you play with my HTFS/VII calculator and keep the base-oil VI under 150.

Thanks, I forgot about those calculators. I played with one of them once and it didn't leave much of an impression on me so I forgot.

iirc, in your .xlsx files you had two HTHS columns. I think one was taking additives into consideration ... Was the main HTHS published and you calculated the other? Can't remember without going back to that thread. I still look at your .xlsx once in a while if I'm dealing with a new oil. I'm still afraid of vii (vm) even if they are new and improved