Hi... I am new Mopar member.. Need help!!

Have a 70 Cuda, and in the process of putting a 440 -6pack!
Found one for sale, Stock rebuilt... with a 6-pack set up ,
Its Carbs to oil pan complete, and heard running!
I am concerned about the YEAR of this engine???
Its is a 1973 Block!

I am not hat knowledgeble on engine 440-blocks..
And which are better year production??

Hope some one has experience and knowledge..
for the big Mopar Blocks to help me!

Thank you so much, Sonny

Sonny welcome aboard. (fasten your seat belt!). See if Andys 440 manifesto is in the archives. EDIT I looked & saw the 451 manifesto which ain't it but someone will point you to it plus offer more info on your Q.

'76 has the thicker main webs.

Mopar used the same casting numbers on the 440 blocks from 1966 to late 1971 blocks. Starting in early 1972 they changed the casting numbers on the 440 passenger car motors only, HD, industrial and marine motors weren't changed
The main thing you need to know about is if that motor is internally balanced or externally balanced If the seller doesn't know see if the crankshaft balancer has a oblong external ring around it or not, if it does it means it is externally balanced and that balancer should say for 440 motors cast into it
If it doesn't have a balancer like that and does NOT shake when running up through 5000 RPM then it is probably internally balanced, The bad thing about externally balanced Mopar V8 is Mopar used external weights on both ends of the crankshaft on the flywheel or converter with weights welded onto the converters
Please let us know what you find out

There are no real 'bad production years' when it comes to B/RB engine blocks.

Nothing wrong with a 1973 block but that isn't a stock engine which means someone rounded up bits and pieces and built an engine. Whether or not they did a good job is the question. My fear is that it is a low performance cast crank short block with low compression pistons that someone added a six pack intake to. If that is the case then it isn't worth very much money. Buyer beware and all of that.......

Welcome to Moparts!!

Keep in mind the later blocks do have a very large bevel on each cylinder.

If it’s priced right snag it. Check to your comfort level.

Unfortunately when you go to sell that car people will get all twisted up, contorted, and maybe have seizures when they find out you put a bad year, off year, or whatever they call it block in it. Because that matters a lot. Just talk to joe average. He’ll tell you. Can’t do that. Not allowed. Against rules. Nope.

“Know what ya shoulda done...”

Edit Cab
Should say "CAST CRANK ONLY"

Not always, the 1970/71 forged steel crankshaft HP motors with the big heavy six pack rods didn't have that written, cast, on them with that external cast in weight

Can a pistons proximity to zero deck be determined without pulling off a head and measuring? The thought of a Six Pack on top of smogger dogger type pistons makes me sad.

welcome to the board sonny ! now you know where to spend all your "free" time.

welcome to the board sonny ! now you know where to spend all your "free" time.

A bore scope can help you determine the pistons, dished or flat tops, there might even be a part number on top of pistons that can be seen. I think it would be worth a try.

In my opinion, all years 440 blocks are just fine unless you have a blower, 3-stages of nitrous, etc. with more than maybe 600-650 horsepower. Also, 74+ blocks use a larger lip on the center main bearing which is preferred, but not required.

Why ... a "six pack" is just a 2 bbl motor until the vacuum kicks in the outboard carbs. And unless you plan to race the thing , who cares if its down on power a bit.

In terms of years of block for B/RB, agree they all can be good. Cylinder wall thickness, verified by sonic check, is a big variable for any block regardless of year manufactured. Also other details about block condition which a good machinist and engine assembler checks.

If you do not know this detail (with confidence) about the engine you are considering buying, buyer beware.

I run a '78 "smogger" block pretty hard and no issues (592 HP/687 ft lb). It checks out OK in wall thickness and other areas. Also the late 400's
had stronger main bearing support vs earlier blocks and in this respect were better.

The ones with the distributor in the front are best.

Kevin