My 56 Thunderbird is a 312 with a manual transmission and overdrive.   The engine is stock.   It was rebuilt and I assume it was bored some amount (TBD).  I plan to update the top of the engine to 57 specs with ECZ-G or 113 heads.   I'm also in the queue for a pair of Mummert aluminum heads.   I have a current version of the Blue Thunder intake manifold with the machining for a larger distributor.  My goal is to build a street 312 with a 57+ camshaft that looks stock to the untrained eye.   I would paint the BT intake and Mummert heads red to match the engine.   John Mummert suggests using 59 and later distributors vs a 57.   Ideally, I would like to use a stock looking distributor that has a mechanical tach drive that connects to the Tbird tach.   But I'm open to anything.  Thoughts appreciated!

I get it.  I've been down the rabbit holes at Mummert / Eaton, etc., for about a decade now.   I would likely sell the Teapot and go with a 4bbl and a 57 street cam.   I had a 57 Ranchero that I intended to build but I sold it, unfortunately, since my spouse didn't like it.   But she's on board with a Thunderbird.   And I kept the wheels and tires from the Ranchero.   Buyer didn't want them.   But they will fit the Thunderbird just fine!

Assuming you have the original axle ratio, I would ask John Mummert what he thinks about using his 280-11 cam, if you will use his aluminum heads. I'm sure Ted could recommend something as well. If you haven't already done so, read Ted Eaton's "Unported Iron Heads Can Still Make Over A HP To The Cubic Inch." The Isky cam selected for that build was larger than what you're considering, even though Karol Miller's Victoria had 3.22 rear gears/w overdrive transmission.  

I'm not sure what the rear end ratio is in the 56 Tbird yet.  It was originally delivered as a 292 three speed manual so it should have a 3:73.   The prior owner later pulled that and put in a rebuilt 312 with overdrive.  And yes, I did read the article about 1 hp per cubic inch in a 292 at Ted's site.    I like his approach, he does no more than necessary but does it the right way.   The Karol Miller build was very interesting.    This was my adventure today, pulling a 272 Marine Y-block from a derelict 1960s Higgins speedboat.  It has ECZ-G heads and Glenwood aluminum marine exhaust manifolds.   Engine is normal rotation, not seized and maybe low hours being a boat.  Total cost $125 but I burned about 12 hours of my time.   It will be interesting to tear into it.