https://www.independent.co.uk/news/science/money-academic-su...
Looking at graduation rates instead of admission rates is problematic. Less gifted and underprivileged people also graduate at lower rates despite being admitted using affirmative action procedures as the College Board is now implementing. This means they do not have a degree that would advantage them, but are saddled with undischargable education debt that puts them at a severe disadvantage for the rest of their life. The system not only continues the inequality but makes it much worse. If college was free or education debt was dischargable in bankruptcy then it would not be the oppressive system it is currently where people unable to succeed are admitted, then forced to pay back debt they can not afford after they fail to graduate. Only a sadist and a racist would support such an inequitable abusive system.
To me it doesn't sound like you're trying to make the SAT reflect say academic potential. It seems like you're just trying to inflate the appearantly already inflated scores of the disadvantaged. Who will proceed to not get scholarships, fail out, and be saddled with debt they can't pay off or be discharged. This of course is the road to an egalitarian society!
Who needs to bother with difficult things like making the disadvantaged do a little better in school? Just add 100 points to their SAT. Problem solved.