If you did a cold test on straight 30 weight oil, it would come up as 30 weight. Like the chart I posted, it would have a dynamic viscosity of 1.53+/- N s/m^2 versus a dynamic viscosity of 0.01 N s/m^2 at 100C.

The only thing that would change that would be adding viscosity index improver to the oil, which would then make it NOT straight 30 weight.

In other words, straight 30 weight oil is ------ wait for it -------- straight 30 weight oil.

Kevin
1951 Chevy 3100 work truck
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1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.