When I chose this cam, I called Isky and they told me the 301333 cam would work with an automatic transmission.  It works great in my car with a manual trans. At this time I am running a Holley 1848-1 465 on a stock iron B intake.  My engine has excellent throttle response and mid range torque. My vacuum at idle is about 12-13 pounds. I don't rev my engine over 5,000 rpm, so I can't comment on high rpm performance.  Choosing a cam is tricky business. I have had street cars with radical cams before. They can grow old quickly.  Some days I feel like I want a race car and other times I wish things were a little smoother.  Better to get it right the first time.  You don't want to change the cam in an early TBird.

I might be comparing apples and oranges, but my brother-in-law's 5.0 Mustang's cam has 220 degrees duration @ .050/w 110 LSA. His power brakes are marginal at low rpm, specifically when backing out of his driveway. The same came/w 112 LSA probably would have been a better choice as far as vacuum is concerned. Although my cam has a 110 LSA, I don't have power brakes. 

If you're still leaning towards the Howard's cam, the part number for the same cam/w 112 LSA is 292002-12. $203.99 at Summit. 

What adapter are you using for 4R70W transmission? Is there sufficient room in transmission tunnel? Electronics/computer?

Long story on the transmission.  About 8 years ago I was thinking about  running a 427 SOHC with a C4.  You can run the same stock Tbird motor mounts on the FE as the y-block.  Everything fit in pretty well, but putting in headers with the stock steering was going to be difficult. 
   This was my dads car.  He bought it from his brother in 1957, and drove it until 1966.  It has sat since then.  I have never been in the car under power, born in 1965.
It was a rust bucket, and not worth restoring.  I bought him a nice 1955 Bird about 10years ago.  He drove it for about 3 years, then started his fight with dementia.  I lost him about 1 1/2 years ago.
  Before he got too bad, he decided he wanted to restore it and give it to my daughter.  We changed plans, and decided to tone it down,  He got to see the finished car, minus the drive train before he passed.  This motor is just a place holder, to mock things up and get things moving.  A mummert headed stroker is in the works. Very delayed due to COVID.
The 4r70w is derived from the C4.  The C4 fit with a ton of extra space.  Not to sure if I will have to massage the trans tunnel for the 4r70w, it is a good bit beefier than the C4.  I am getting a Bendtsen Speed Gems adaptor.  The electronics will be controlled with a Baumann controller.  

Paul

Every year, a 1955 T-bird is entered in our annual downtown car show. There is a SOHC 427 under the hood, but I think the only original part left on the car is the body. Nevertheless, it's quite impressive, especially knowing I'm looking at a $50,000 engine.

I have had the SOHC for over 20 years.  I didn't pay anything near that for it.  I guess it was a good investment.  I should tell my wife, might make up a little bit for what I have spent on the Bird so far.  It really was a rust bucket.  I already have spent twice what it is worth getting it this far.  It is a very early car, #34 built.  I was told the first 100 cars were made per production line, and have a bunch of little differences.

Paul

Just another option for you, i am using a isky 301974 i got from mummert 216 degrees intake and exhaust  at .050.  Lobe center 111degrees. 
installed at 110. Its in a 304 with ecz c heads. I am running power brakes and a aod.  No problem with idle or vacuum to power brakes. 
Good street driver.  Hope this helps. 

Located in Harford County Maryland 

Is that the Cam Mummert calls the '57 + ?


Paul

I have read that you can swap an FE into an early Tbird using the stock YBlock mounts.  I am curious, did you mount the cammer using the YBlock front mount and steady rests or did you fabricate new frame side mounts?

The early Fe equipped pick up trucks used a front mount like the y-block.  To put a wedge FE in the bird you  get the timing cover (iron) and the front mount from an early FE truck.  You can use the bird strut mounts.  Everything lines up, and is a simple bolt in.  It locates the motor in the same place as a y-block.  With the cammer you use the same front truck mount, but you can'y run it with the stock timing chain cover.  I had DOVE cast up a front cover where the lower block section was like the FE truck timing cover.  I knew Jim Dove pretty well, and it was a simple mod to the casting.  I could have machined up an adapter plate for the mount, would not have been too hard.  Just need a level surface to mount the truck front plate to.  Dove had a 57 bird with a 428 FE in it with this mount set up.  It looked like a stock factory install.

Paul