Cliff's Quadrajet Parts and Rebuild Kits

Rick, the idle bypass air is routed differently on these units with the HIC in that location.
Marked in blue circles.

 Interesting, I wasn't aware of that. Never would have guessed that's how they routed the idle by-pass air. I'll have to take another look at my early Cadillac carbs.
 Thanks Kenth.

 So eventually I'm going to be using a '69 472 in a '56 Cadillac, but I'd prefer to use a newer carburetor on it with the APT.
  I have both of these carbs, 17057231, and 17059232, but they're calibrated for a 425, and both have the primary side POE system. Is that calibration acceptable for a 472, or would they need to be "tweaked" a bit, and if so, exactly where?
 I do have multiple original '69 Cadillac carbs, and if memory serves they do not use the POE system for the primary side.
 However I don't know if the specs for an early design would necessarily work on the later one due to design upgrades.
 Any thoughts on how to proceed?

 Rick

Too bad Edelbrock did not use the Rochester cast letters in their chart.
H is the only port they got right.

Good to know. As I am just trying to learn about Qjets, I took that at face value.

Suprchy

To all,

Here are the Photos I have;

1.) 7042238 Airhorn Topside Pin is from the internet and shows the pin from a top down view.
2.) 7042238 Airhorn Underside Pin is from my 7042238 and shows the pin from underneath the airhorn.
3.) 7042238 Float Bowl Cavity is from my 7042238 and shows where the valve would be if it were there?

This is just my best guess so please jump in and correct me if I am wrong. I do not want to add to the misinformation that is already out there. I am just trying to figure this carburetor out.

Does this valve/compensator look like the ones that go into the rear cavity or are they different? I don't see how they could be the same if that is indeed where it fits on this carb.

Thanks for all the info,

Suprchy

Too bad Edelbrock did not use the Rochester cast letters in their chart.
H is the only port they got right.

 I just got back from Tucson, and checked the lettering Edelbrock used. You're right, but why in the heck would they arbitrarily give each port a different letter designation, when it's obvious that Rochester had already done so.
 If someone wasn't paying attention to that, they could get really messed up.
 Thanks for pointing that out Kenth, I probably wouldn't have noticed that until I tried using their chart for reference. Good catch.

 Rick