About 1965 Mustang 289 A code 4V Engine (Fastback 2+2)

Hello,
I have 1965 Mustang Fastback 2+2 (289 ci 4V A code).
I read some magazines and internet sites about my car engine specifications, but there are conflict about "Compression Ratio" and " Horse Power". According to some magazines 1965 A code 289 4V engine's Compressinon Raito is 9,3:1, some of them 9,0:1 end rest of them 10,0:1. Could you give me detail information about certain numbers about my engine specifications and if you have, pls attach scanned offical Ford Mustang documents about 289ci small-blocks engine (1965 Mustang Specific).
Best Regards
 
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I think what you are running into is the mixing of 64 1/2 and 65 models (or early 65 /late 65).

The early 65's 289 was 9.0:1/210HP and a 5 bolt bellhousing block. (D code/4brl)
The late 65's 289 was 9.3:1/200HP and a 6 bolt bellhousing block. (C code/2brl)
The late 65's 289 was 10:1/225HP and same C code block, but with flat top pistons. (A code/4brl)

What you have to remember, is that both the blocks and the heads changed from early 65 to late 65.

Also, the D code was early 65's version of the late 65's A code (both are 4brl engines).

The book I am using is Cars & Parts Catalog of Mustang ID Numbers 1964 1/2-93. Sorry, I don't have a scanner.

Lastly, you will have a very hard time finding A code specs, because they are all the same as the C code except for having flat top pistons, 4brl intake and 4brl carb.

I have an A code 65 as well, but have found little information on it. A codes are a bit of an over looked option in favor of the K codes, unless of course your A code was a GT.
 
That book looks right, but mine is blue instead of yellow. ISBN 1-880524-10-4

As for the details, I don't know. I read somewhere that over 15,000 65 GTs were made and double that for 66. I have also read that no option specific production numbers exists until 1967 (aka martini reports start here).

Since not all K codes were GTs, I venture to say about 10,000 GTs were A codes, but this is a complete guess.

I've seen a lot of Autolite 4100s running around, so a lot of A code Mustangs (and K code Comets) had to have been made.