Difference in pronunciation of "a team" and "A team"?

I noticed that I pronounce the A differently based on the intended meaning:

I belong to the A-team. (like ey in they)

and

I belong to a team. (like a in apple)

Are the pronunciations supposed to be different or is it an artifact of how I have learned to pronounce the alphabet and the article?

In this case, when the vowel a is pronounced long and capitalized, A is an ordinal. The A Team is superior to the B Team. (you rarely hear about the C or later teams.)

A-team: A group of elite soldiers or the top advisers or workers in an organization.

Oxford Dictionaries Online

B-team is usually derogatory

Derived from high school varsity and junior varsity sports, where the "B Team" is made up of the stragglers and uncoordinated losers. Used in a situation in which someone drops, breaks, messes up, stutters during an insult, or just acts a fool.

Urban Dictionary

There was a television show in the US for several years called The A-Team. They were a group of very effective, but unconventional heroes who solved intractable problems (usually with both force and guile). Wikipedia

Although many dictionaries offer a long a pronunciation for the indefinite article, in common speech it is almost always pronounced short, as a schwa.

Oxford Dictionaries Online

The article a is pronounced in many ways, but it is rare to pronounce the letter A in any way besides the ay from "play". Using the International Phonetic Alphabet, the capital A is almost always pronounced as /eɪ/. The article a may be prounounced as /eɪ/ ("play"), or it may be relaxed to /ʌ/ ("run"). (Note: some feel this is better represented as /ə/, which is an unvoiced vowel such as "comma", but its not agreed whether there is even a difference in English phonology, so if "run" and "comma" appear to have the same pronunciation to you, don't worry about this detail.)

In general, you will find English speakers relax a to be pronounced /ʌ/. However, you will find it pronounced /eɪ/ for emphatic reasons. You'll see this most often in cases where a sentence is worded ambiguously, and the extra stress on a will be used to draw the listeners attention to the fact that you're about to use the exact wording of their sentence very carefully.

If you're talking about "a team," (lower case), you are talking about a "random" team. (The a is pronounced as in America, which is to say as a "short" a.)

If you're talking about "the A team," you're talking about a "non-random" team that is "the best" or "number 1." The letter "A" (upper case) is synonymous with this, since A comes first in the alphabet. Then you use the long "A" (preceded by the word "the" for emphasis (since there is only one A team.)