What does it mean?

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Holy Roller

Holy Roller

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What is a " low deck" engine. I saw this term in a intake manifold description. Can someone tell me what this means and how it would effect the choice of my intake. Thank you
 
383 & 400s are low deck big blocks. B engines
413 & 440s are RBs or raised blocks
The deck height is what has been raised.
This makes the intake manifolds specific to B or RB one or the other.
 
Mopar 350,361,383, and 400 were all "B" engines, or low deck. 413,426, and 440 were all "RB" meaning raised "B" engines, due to the taller blocks, requiring a different intake and distributor. There was also an " RB" 383, from the late 50's I think. Very few were made.
 
The term also applies though less used to the 170 slant six.

The 170 is an LG "low G" engine ......a.k.a. "low deck six"

the 225 is an RG which means "raised G" because the stroke made it taller.
 
To further explain, "low deck" engines are shorter stroke, RB "raised block" or "high deck" engines are longer stroke. A popular "mod" nowadays is grinding out clearance in the pan rails in a 383/ 400 block and put a long stroke crank in the thing, making a "low deck" stroker.
 
I love learning new things, I really appreciate all the helpand I'm sure I'll have plenty more questions before it's all said and done. Any suggestions about Offenhauser 360 low profile intakes.
 
Mopar "B" engines are all "low-deck" being the 350, 361, 383 and 400. The "RB" engines were the 413, 426, and 440 meaning high deck, ALL are "Big Blocks" just the intake height is different requiring specific intakes for the 2 types. In 1959, Mopar (Chrysler) had to figure out how to change between engines types in a timely manner and had for that year BOTH a 383 "B" block as well as a 383 "RB" engine, also said above.

"B" blocks are Big Blocks, and "RB" "R"aised "B"lock engines. As mentioned the RB's had a longer stroke, where-as the B engines had a shorter stroke.

Then, you had the "A" engines, Mostly Poly-Head engines (special combustion Chamber, Semi-Hemi), heavy cast blocks. BUT, then you had the "LA" meaning "L"ight "A" blocks that were the 273, 318, 340, and 360.

The Slant 6's somewhat followed as the "LG" 170 "L"ow "G" block. The "RG" 198 AND "RG" 225 were "R"aised "G" blocks.

The early true Hemi's were A blocks (I THINK) I haven't seen any "letter" destination on them, BUT that changed when the 426 Hemi came along as it was an "RB" Hemi as the second generation Hemi engines unfolded in '64. The 426 Hemi was built off the existing RB 426 Wedge-Head engine.

The Early A blocks of the Poly-Head design, also could have had special ordered Hemi Heads bolted onto them. Replacing the Polyspherical heads, to make it a true Hemispherical head.
 
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