Hi 65mustangman,
The Stovebolt $65 carb is probably the Holley-Weber 5200. I say probably because I am under the impression that he is now selling Motorcraft 2100's at this price.
The 5200 is a 2V progressive that flows 270cfm. It is easy to tune as parts are easy to get (jets, etc.). I favor progressives because they tend to lower the torque curve (stronger bottom end). I have a Stovebolt 5200 and I am very happy with it. However, I have never seen one set up as a direct mount. No reason why this can't be done. Just not aware of any having been mounted this way yet.
The 2100 is available in several flow rates. The 1.08 seems to be the most popular (280cfm). While not progressive the throats are small enough to keep low rpm intake velosity high enough to produce a good bottom end. This carb, and the Holley 2300 (350cfm), are the most common direct mount units. They have the same mounting pad, so they are interchangable. The 2100 is more difficult to tune to a specific application as jets are hard to get. No problem with the 2300, which is also available in a 500cfm version.
Since the cam you are using is advertised to 5000rpm, and assuming that your cam, head and header mods will raise your VE to 85%, your max flow requirement will be 280cfm. This is a little on the high side for either the 5200 or the 2100 / 1.08. If you want to stay progressive (I like progressive) you can go with the Weber DGV (32/36) series. They fit the same mount as the 5200 and flow 320cfm. The 2300 would also do the job for you, but there my be an off-the-line advantage to the Weber.
Hope this is helpful - Steve
