Of course it is, creating that difference was the basis for IQ testing in the first place.

Are they consistent across time and cultures? Are they corrected for differences in health, education, culture, wealth, etc? How big are racial differences compared to differences between people from different social classes?

How do you define racial groups? its something that constantly shifts. I have an encyclopedia for the 1950s that defines South Asians as "Caucasoid" which is not how most people now think.

Based almost entirely on racist studies, including some famous ones that were comparing white and black school children in apartheid South Africa. I wonder if there may have been some confounding variables there, but surely this is just my bias.

Plus, none of these studies actually spend the money to do any genetic testing, they simply assign people to "white" or "black" race based almost always on skin color (which, since the gene for dark skin is dominant, is a very poor marker of actual genetic similarity - the great grandchild of a dark-skinned person with otherwise only white-skinned relatives can still be dark-skinned).

Edit: and I'm not even mentioning the obvious publication bias, as essentially only racists care about this race vs intelligence discussion, at least enough to invest in creating studies about it. Plus the fact that IQ itself is actually a very problematic measure, when applied beyond its actual medical use (quantifying mental disability).