Road & Track ND V8 road test
The test you're looking for is in the "Outrageous Issue" of Road & Track, June 2019. It will hit subscribers the week of May 13th and be on newsstands starting on the 21st. We'll post links to it as soon as it's available online.
In the meantime, you can see all of our previous tests here: Flyin' Miata in the news