351C where to start?

[giantpune]

There's not a whole lot to decode on that vin. Its only a partial. I think you already got the year-1973 and the plant was Atlanta. The rest is the sequential car number it came from. There were a handful of cars that came with a 351C, made in Atlanta in 1973. That could possibly be a ranchero or maybe a gran torino?

Nothing about that suggests that the block is not worth the effort. You may be dealing with a rebuild motor, or somebody could have pulled a complete motor out of a different car to plop in.

 

[Stanglover]

I'm not sure about the engine block casting letter "A".
If that motor is otherwise good, it probably should be a 4 bolt main, not that the extra bolts actually do much, so could well be worth rebuilding to whatever spec you want, keep it stockish or stroke it.
I'm definitely not the engine guy around here, so I'm sure others will chime in to help out.
One thing is for sure, you don't have the original motor in there.

 

[351mach1]

Block Casting is D2AE-CA
Production Date: 2k26 (26 September 1972?)

According to Enginelabs.com: D2AE-CA – 1972-1974, 1971-1974, 351 Cleveland small-block, 4-bolt mains, High Output, Cobra Jet, Boss

I know I need to look in the pan to verify 4 bolt main but that's cool. So how do I figure out if I'm working with a high compression 72 HO or a detuned 73 CJ? I'm really kicking myself for not getting head casting numbers. I guess I can use borescope to peak in the oil drain to verify 4 bolt, peak in the spark plug hole to see flat or dished pistons, maybe be able to tell if open or closed chamber heads (but guessing from production date probably open chamber)?

I know this could all be a moot point if the engine was rebuilt before and the only absolute way to tell is to tear the engine apart; just trying to get as much info as possible to figure out where to steer this ship. Next up is to order the timing set and try to get it running correctly. Any thing else I should order or be on the lookout for while I'm in there?

Edit: I am kinda getting hung up on whether this is the higher compression engine or the low output 73. How big of a difference is it really? I am not ready to do a full engine overhaul so just hoping im starting with a better foundation.

 

[boilermaster]

351mach1,
The 1972 HO engine (as delivered) should be a solid lifter engine and therefore (should ) have screw in rocker studs and adjustable rocker gear with open chamber heads.
The CJ (should) have hydraulic camshaft, pedestal rocker arms and open chamber heads.
Boilermaster

 

[Stanglover]

I have a theory as to why nearly all 72-73 351C motors had 4 bolt mains;
As ALL the blocks cast could be drilled and tapped for the extra bolts, Ford produced way too many 4 bolt caps. Only certain 70-71 351C blocks got the 4 bolt option. The M code was only 2 bolt for example.
SO, as they had all these extra caps on hand and as the production line was already set up to add the extra 5/16-18 tapped holes, why not use them up.
From what I understand, the smaller bolts are there only to stop or reduce fretting, sideways movement, so do little or nothing to add strength. The main bolts hold it all together.
As for your motor, for now, get it running and worry about what's in it later. An option might be to pick up a 351C block and build your own motor later.