[unruhjonny]

As a disclaimer, all we can do is guess.

Unless you find info, and great photos from the people who were actually at the tests, we are left to guess.
Keep in mind they were journalists, not super fans of these cars - so expect some of the minutia to be lost...

By my estimation, for the early press gathering, there were three or four performance Firebirds on hand for testing - these cars would be the ones in print for the February/March magazines.

1) white TA; Deluxe interior, no console, pre-production shift knob, no A/C, RAIV, 4spd; 3.90:1(?) gearing (possibly the same car used for advertisement photos)
2) red(?) Formula; deluxe interior, console formula wheel, A/C, std engine, auto 3.08:1(?) gearing
3) blue(maybe??) Formula; RAIII (this car gets very little ink*, but may be the blue Formula used for '70 sales/promo images)
4) yellow Formula; std engine - nothing clearly mentioned about this car.

Now, the Trans Am shown on page 34 of the February Hot Rod article is a white car;
It seems that same white car is pictured in much better detail in the March Super Stock article.
Did you notice that the Trans Am mentioned in the HR article had a non-production 3.90:1 gear set?
Non factory gear set, and e/t's a full half second or better than other recorded e/t's from Firebirds for the early articles - that to me says something right there.

* = Regarding the untested(?) ram air Formula;
the ram air boots shown on page 21 of the Super Stock Magazine issue are clearly pre-production pieces.
The HR article mentions a 3.31:1 geared auto Formula (I believe that this was a gear set used on auto/RA cars), while the Super Stock article mentions a four speed 3.90:1 geared Formula (this tells me it's a pre-production car);

The oddball test(?) car was the yellow Formula;
Other than some photos, this car is a mystery to me.
This car has non-production door handles, non-production single chrome rear view mirror shown, and the dealer-install-only hood tach(!);
This car is on the cover of the Hot Rod article, and more photos of it are in the April 'Cars' article.
Maybe this is the other 3.90 geared four speed Formula??

After these initial articles, it appears as though the red Formula stayed a part of the test fleet, but the TA was changed from a pre-production car to a production car with a console (and the black ball shift knob) for the June print date articles.
To punctuate why I believe that the June printed TA was a differnet car than the one shown for February/March magazine articles, and not just a refreshed car, you need not look further than the June 'Car Life' article;
Very little is shown, or explained about the TA, but with only a 14.51 @ 99.3mph e/t - it simply has to be a different car.

I have read (I cannot recall off hand where), that some of the writers at this time would estimate e/t's - this may serve to explain why the June Car Life, and June Car and Driver magazines had 4/10 of a second difference between them;
Surely they wouldn't be the same car...??

I think the red Formula was also the car used fot the single 1971 Firebird road test;
It was in a UK magazine, and between the mention of the need for premium fuel, and other photos, it seems to clearly be a 1970 model.