Mopar engine differences

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OldJoe54

OldJoe54

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The more I learn about mopar topics, the more I learn there are more topics to learn about. So as I talk to people, research different things, I come across people saying "short block", "long block", "big block", and "small block". This may be all semantics or they might all be a real thing. Can someone either explain the differences, or if it is too long of a discussion, can you point me to a site that can explain it all? Thanks.
 
Long/Short has nothing to do with size
Short Block = Block with crank cam and pistons, no heads
Long Block = Above with Heads

Modern era
Small Block (Mopar) 273, 318, 340, 360
Big Block (Mopar) 383, 400 440 (426)

Alan
 
Short block is an engine assembly without the heads, a long block includes the heads and valvetrain. It used to be if you blew your bottom end you couled order a short block from a reman house and swap your top end over. Big/Small block is sort of self explanatory different cast blocks to handle different bore /stroke configurations ,Ill go out on a limb here andsay a small block is up to 4 inch bore big block is bigger than 4 inch bore typically hence the need to cast a beffier block. Im zsure someone woill be along to say everything I just typed is wrong but thats how I remember it from my time in the wrench biz...of course ever since the internet everything I know has somehow changed :)
 
Cuda Al said:
Long/Short has nothing to do with size
Short Block = Block with crank cam and pistons, no heads
Long Block = Above with Heads

Modern era
Small Block (Mopar) 273, 318, 340, 360
Big Block (Mopar) 383, 400 440 (426)

Alan
Click to expand...
I love the "Modern Era" tag- for engines pushing fifty years old. That's kinda dating ourselves, eh?
:lol:
 
To expand small blocks have the distributor in back and big blocks have it in front.
 
"Modern era" small block stroker can be 390, 408, 416, 426.
 
69conv said:
To expand small blocks have the distributor in back and big blocks have it in front.
Click to expand...

...except Hemi was different. Early Hemi had the distributor in the back, 426cid Hemi had the distributor in front.

Chrysler early Hemi displacements: 331, 354 and 392cid
DeSoto early Hemi displacements: 276, 291, 330, 341 and 345cid
Dodge early Hemi displacements: 241, 270, 315 and 325

Check out Chrysler Hemi engine - Wikipedia for additional details and engine applications.
 
Short block and long block can mean different things. Short block means an engine with no heads. It might have camshaft, it might not. It totally depends on whose short block it is. It might have oil pump and pan. It might not. It might have timing cover. It might not.

Long block means engine with heads. It might have the complete valve train. It might not. It might have all of the tin like oil pan, timing cover and valve covers. It might not. It's all dependent on what company offers it and how they offer it.

Small block and big block are technically defined by the bore spacing. Chrysler engines are pretty easy to differentiate. Big blocks have distributors in the front, small blocks in the back. Early hemis (51-59) are generally considered small blocks, since their blocks are almost exactly the same size as the A and LA engines, although they are simply referred to as "Hemi".

Second generation Hemis (the 426) are big blocks, since they are based on the Chrysler RB (raised block) engines.
 
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Cuda Al said:
Long/Short has nothing to do with size
Short Block = Block with crank cam and pistons, no heads
Long Block = Above with Heads

Modern era
Small Block (Mopar) 273, 318, 340, 360
Big Block (Mopar) 383, 400 440 (426)

Alan
Click to expand...
For big blocks you forgot the 350, 361, 413 and the 2G Hemi.
 
I have received a lot of great answers to my question, plus I took advice and went to Wikipedia and another web site for info. I especially like the way the replies turned amusing as they went on. Once again everyone for making me smarter, and I just want to say before this thread I never used to be a engine builder, but now I are one!
 
I always have apppreciated people who are new to the Mopar family and ask relevant questions. The Mopar engine families have pretty much led or followed the lead of other manufactorers. Most answers in this forum have been informative, particularly the difference in a long block or short block. Standard of the industry. Mopar small blocks (LA) were listed in cubic inch displacement from 273-360. and all did have rear mounted distributors. The term "big block Mopar" can refer to all the engines people mentioned from 350-440 cubic inches with front mounted distributors. From this group, you could also have B or (Low Block/deck height) and RB (Raised Block/deck height. That is basically the 3.31 stroke vs 3.75 stroke. Another significant difference that most people take for granted is the deep skirted crankshaft placement within the confines of the B or RB engine. This contributes significantly to strength and weight differences from A blocks vs B and RB blocks. All great engines. Great question.
 
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Cuda Al said:
Long/Short has nothing to do with size
Short Block = Block with crank cam and pistons, no heads
Long Block = Above with Heads

Modern era
Small Block (Mopar) 273, 318, 340, 360
Big Block (Mopar) 383, 400 440 (426)

Alan
Click to expand...
I could be wrong but a 440 and 426 Weg is a Raise block (RB) and not called a Big Block (BB), the 426 Hemi is a class of its own. Don't forget the 413 RB.
 
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