Thanks to http://www.geocities.com/musclemopars/brbblock.htm

B / RB Engine Blocks
Chrysler's "B" and "RB" engine blocks are extremely sturdy. The block casting  uses extensive support webbing in the mid and lower areas. The main bearing bores are supported by the  block sidewalls which extend past the crank centerline more than 2 inches. Additional webbing to support the main bearing bores make the block very rigid without excessive weight. Bare block castings weigh in at about 215 pounds for the "B" engine and 225 for the "RB". The primary differences between the "B" and "RB" blocks are the main bearing bore diameters (2.625 for the "B", 2.750 for the "RB") and the crank centerline to deck surface dimensions (9.980 for the "B" vs. 10.725 for the "RB"). Rod journals are the same for both engines.

Interchange between the engines is exceptional. Both use the same 4.80 inch bore spacing and the same cam to crank spacing. The heads, timing chain, camshaft, oil pan etc. interchange completely. Intake manifolds don't interchange due to the difference in deck heights.

 
B&RB Bore/Stroke Combinations
CID Bore Stroke Series
350 4.060 3.380 B
361 4.120 3.380 B
383 4.250 3.380 B
400 4.340 3.380 B
383 4.030 3.750 RB
413 4.180 3.750 RB
426 4.250 3.750 RB
440 4.320 3.750 RB

How to Identify Mopar B&RB Blocks

Engine Block Stamping #

On "RB" engines the cubic inch displacement is stamped on a pad located at the front of the block. "B" engines have a similar pad located on the right side of the block near the base of the distributor.  Engine displacement, performance level, undersized bearing journals, oversize cylinders and other special information are also identified here.
Decoding Engine Block Stamping #'s

1960-1964 

From '60 to '64 a typical engine ID code will look like this: S42-222
The first digit identifies the year: S=1962
The next 2 digits are the first 2 digits of the engine CID: 42=426
The last 3 digits are the date and month: 222= February 22

1965 - 1971

In '65 the third digit of the CID was added to the engine ID  code. 
After '65 a typical engine ID code will look like this: B383-322
The first digit identifies the year: B=1966
The next 3 digits are the engine CID: 383=383
The last 3 digits are the date and month: 322= March 22

Year Codes for B & RB Engines
  • A - 1965
  • B - 1966
  • C - 1967
  • D - 1968
  • E - 1969
  • F - 1970
  • G - 1971
  • H - 1972
  • J - 1973
  • P - 1960
  • R - 1961
  • S - 1962
  • T - 1963
  • V - 1964
  • 4T - 1974
  • 5T - 1975
  • 6T - 1976
  • 7T - 1977
  • 8T - 1978

Other Stampings
Additional stampings may be found on the ID pad.
They identify non standard engine components. 

A - .020 oversize cylinder bores
Diamond - oversize tappets
E - Cast Crankshaft
HP - High Performance
L or LC - low compression
M - .001 undersize main bearing journals
Maltese Cross - .001" undersized bearing shells
Maltese Cross and an X - .010" undersized crankshaft
O.S. - .005 oversize valve stems
P - premium fuel
R - regular fuel
RX or MX - all main or rod journals .010" undersized
S - special engine
WT or TW - water test
X - .010" undersize crankshaft
'68 and later B&RB engine serial numbers

Beginning in 1968 all Mopar B&RB engine blocks have an engine serial number stamped in the left side oil pan rail at the rear corner under the starter opening.

Sample Serial # PT44028650001

 Plant Code: PT

  • MV,MN - Marysville Plant (426 Hemi)

  • PT - Trenton Plant (361, 383, 400, 413, 426, 440)

Cubic Inch Displacement: 440

  • Should need no further explanation

Date Code: 2865

  • Based on 10,000 day Julian Calendar

  • 2865 is June 1, 1969

Serial Number: 0001

  • A sequential number for each days
    production beginning with 0001

 

Matching Numbers?

On 1968 and later engines the numbers stamped on the lower rail of the engines right (passenger) side match the last 8 digits of the cars vehicle identification number. This confirms that this is the original engine. The matching numbers add to the cars value.

Engine Block Casting # and Date Code

The date code and block casting numbers are found on the left side of the block. This block bears the casting # 2536430. The following chart identifies it as a 66 - 72 440 block. The casting date of 2-26-69 indicates that this is a '69 block.
B / RB Engine Block Casting #'s

Casting #

Application

Type Engine
1944929 Chrysler - Dodge - Plymouth B 58 350
1737629 Chrysler - Dodge - Plymouth B 61-64 361
2205712 Chrysler - Dodge - Plymouth B 58-66 361
1851729 Chrysler - Dodge - Plymouth B 59-64 383
2120329 Chrysler - Dodge - Plymouth B 59-64 383
2468130 Chrysler - Dodge - Plymouth B 59-71 383
3614230 Best 400 Block - Heavy  Main Webs B 71-72 400
3698630 Chrysler - Dodge - Plymouth B 73-78 400
1852029 High Performance & Truck RB 62-413
2120529 Chrysler - Dodge - Plymouth RB 59-65 413
2205697

Chrysler - Dodge - Plymouth

RB 59-65 413
2205697

Chrysler - Dodge - Plymouth

RB 64-426
2406730 Max Wedge RB 63-65 426
2532230 Max Wedge RB 64-66 426
2658836 Industrial RB
2536430 Chrysler - Dodge - Plymouth RB 66-72 440
3698330 Chrysler - Dodge - Plymouth RB 73-78 440
4006530 Chrysler - Dodge - Plymouth B 76-78 400
4006630 Chrysler - Dodge - Plymouth RB late 75-79 440

 

Big Block Cylinder Heads

Since 1958 there have been 14 different head castings. All B/RB heads interchange which makes swapping easy. However, swapping the '62 to '64 Max Wedge heads onto a "B" engine isn't recommended because there are no intake manifolds available for that combination.

The '67 440 and '68 to '70 383 and 440 4-barrel heads are considered the best factory heads. The '67 heads have a smaller "closed" combustion chamber and can be used to increase the compression ratio on later model low compression engines. Care must also be taken when swapping the '67 heads onto the '68-'69 383 due to the lack of piston to chamber clearance. The 383  has a positive deck height. (the piston protrudes above the  block deck surface) The deck height has to be at or below the deck surface to provide the necessary clearance.

Location of Cylinder Head Casting #'s

The casting numbers for Mopar Big Block cylinder heads can be found on the underside of the head on an intake runner. (upper photo)

The casting number can also be found under the valve cover on an intake runner. (lower photo)

Big Block Cylinder Head Part #'s

Casting#

Part#

Engine Chamber In  Ex 

1737637
1944705

2128533

58-59 361 Closed 1.94

1.60

1737637 2448752 60 361/383 Closed 1.94 1.60
2206324
2206924
2128589 61-62 361/383/413 Closed 2.08 1.60
2402286 2402358 62 413 Max Wedge Closed 2.08 1.88
2463209 2406754 63 426 Max Wedge Closed 2.08 1.88
2463200 2448752 63 361/383/413 Closed 2.08 1.60
2406518 2406736 64 426 Max Wedge Closed 2.08 1.88
2406516 2406732 64-67 361/383 Closed 2.08 1.60
2406158 2806019 67 440 Closed 2.08 1.60
2780915 2800762 67 440 HP Closed 2.08 1.74
2843906 2843904 68-70 383/440 Open 2.08 1.74
2951250 2843904 68 440 Open 2.08 1.74
3462346 3462344 71-72 383/400/440 Open 2.08 1.74
3462346 3671640 73 400/440 Open 2.08 1.74

3751213

3751218 73 400/440
Motor Home
Open 2.08 1.74

3769902

3769910

74 400/440 Open 2.08 1.74

3769975

3769954

75 400/440 Open 2.08 1.74

4006452

3769954

76-78 400/440 Open 2.08 1.74

Pre '64 heads are easily identify because they use only 4 valvecover bolts.

Big Block Mopar Crankshafts
Chrysler's "B" and "RB" engine crankshafts have two basic stroke dimensions. The "B" engine crankshaft uses a 3.380 inch stroke and the "RB" engine uses a 3.750 inch stroke. Main journal size also differs between the "B" and "RB" engines. The "B" engine uses a 2.625 inch main journals, the "RB" uses  2.750 journals. Both engines share the same 2.380 inch rod journals.

All early crankshafts are steel forgings. In 1971 Chrysler used a cast crank in low performance 383 engines. The use of cast iron crankshafts in 440's began in 1972. All cast cranks and certain forged steel cranks are externally balanced. These require the use of specially balanced harmonic dampeners, torque converters and flywheels. The appropriate components  must be used to ensure that the reciprocating assembly is in balance. If an internally balanced crank is used with an external balanced converter or dampener (or vise- versa) a severe out of balance condition  will occur. Externally balanced crankshafts can be internally balanced by adding a heavy metal called Mallory metal to the crank throws. 440's equipped with 3x2 barrel carbs were also externally balanced to compensate for heavier rods. They require the use of externally balanced dampeners and converters or flywheels.

 

 
Big Block Mopar Crankshaft Part #'s
Part# Engine Material Comments
2268114 383 4BBL Forged
3462922 383 / 400 2BBL Cast Externally Balanced
3672000 400 4BBL Cast Premium Cast Crank
Suitable for mild hop-ups
2536983 67-71  440 4BBL Forged A good general crankshaft
3512036 70-72 440 6BBL Forged Externally balanced
premium crank
3671283 72-73 440 4BBL Forged A good general crankshaft
3671242 73 440 4BBL Forged Balanced for different
weight pistons
3751889 74 440 2&4 BBL Cast Externally balanced
3751899 74 440 HiPo Forged A good general crankshaft
2406240 413/426 Max Wedge Forged Best RB crankshaft
Big Block Crankshafts Dampers
Part# Application
2658457 1958-1971 All B & RB engines
3512017 1970-1971 440 6BBL and '71 440 High Performance
3577180 1971 383 2 barrel (cast crank)
3614371 1972-1973 400 Forged Crank
3614374 1972-1973 400 Cast Crank
3614371 1972-1973 440 Standard Performance
3614372 1972-1973 440 High Performance
3577785 1974 440 Cast Crank

72 and up B&RB dampers use a different pulley bolt pattern.

 
Degree your damper
A degreed damper is useful for setting total spark advance and for valve lash adjustments when using a solid lifter camshaft. All Mopar crankshaft dampers have the same 7.25 inch diameter. You can mark your damper with a self adhesive timing tape or mark it yourself using the following dimensions.

Mark your damper in the direction of rotation (1/16 inch = 1)

Degrees Distance Purpose
28 1 3/4" Setting Total Advance
30 1 7/8"
32 2"
34 2 1/8"
36 2 1/4"
38 2 3/8"
40 2 1/2"
42 2 5/8"
103 6 1/2" Setting Cam Centerline
105 6 5/8"
107 6 3/4"
109 6 7/8"
111 7"
180 11 3/8" Setting Valve Lash
Big Block Connecting Rods
The connecting rods used in B and RB engines are of a typical I-Beam design. Other design features include pressed fit wrist pins and 3/8 inch cap bolts. Dimensions of the "B" and "RB" rods are similar with the exception of the center to center length. the RB rods are .410 inches longer. The rods have nearly the same cross-sectional area and use the same rod bolts but the b engine rod is capable of higher rpm abuse because a shorter beam area can tolerate greater loads. The shorter beam area and the reduced loads  of the B engines shorter stroke allow reliable operation in the 6500-7000 rpm range for stock rods. Due to higher loads induced by longer rods and crankshaft stroke, the RB rod should be limited to 6000-6200 rpm

 

Big Block Connecting Rod Part #'s
Part #

Engine

Length

2406766

64-71 383
64-66 361
72-74 400
6.358

2406770

62-64 413
62-64 426 Wedge
68-69 440 4BBL
70-74 Except High Performance
6.768

3462426

69 440 3x2 BBL 6.768

2951906

70-74 440 High Performance
70-72 440 3x2 BBL
6.768
 B Engine Intake Manifolds
Engine Year Comments Casting #
383 2x4 59-61 1827899
383 4bbl 60-67 2205968
383 4bbl 68-69 2806301
383 4bbl 70-71 2951666
400 4bbl 72 3614046
400 4bbl 73 3671879
400 4bbl 74 3698442
400 4bbl 75-76 3830949
413 4bbl 59-65 2206000
413 2x4 59 300E 2264877
413 2x4 62 300H 2266487
413 2x4 62 Max Wedge / Aluminum 2402726
413 2x4 63-64 Crossram / Left 2421369
413 2x4 63-64 Crossram / Right 2421368
413 2x4 63-64 Crossram / 300J-300K Left 2129987
413 2x4 63-64 Crossram / 300J-300K Right 2129985
413 2x4 63 Max Wedge Stage ll Aluminum 2402728
413 2x4 64 Max Wedge Stage lll 2402720
 RB Engine Intake Manifolds
Engine Year Comments Casting #
426 2x4 65 Max Wedge / Aluminum 2406185
426 2x4 64 Max Wedge / Aluminum 2465165
426 Hemi 66-71 Street Hemi 2780543
440 4bbl 66 2206000
440 4bbl 67-69 2806178
440 4bbl 70-71 2951736
440 4bbl 71 3512501
440 4bbl 71-72 3614014
440 4bbl 73 3698444
440 4bbl 74 3751721
3830733
440 4bbl 75-76 3830733
440 3x2 69 Aluminum 3412046
440 3x2 70 Aluminum 3418681
440 3x2 70-72 Iron 2946275
2946276

 

B&RB Engine Exhaust Manifolds
Engine Year Comments Casting #
350-361 58 Right 2205535
350-361 58 Left 2205536
361 59 Right 1739599
361 59 Left 2205536
361 60-64 Right 2205535
361 60-64 Left 2205536
383 59 Right 1739599
2205535
383 59 Left 2205536
383 60-64 Right 2205535
383 60-64 Left 2205536
383 65 Right 2205535
383 65 Left 2461307
383 66-69 Right 2532464
383 66-69 Left 2461307
383 68-69 Cuda & Dart / Right 2863000
383 68-69 Cuda / Left 2899002
383 68-69 Cuda & Dart / Right 2863900
383 68-69 Cuda & Dart / Left 2946720
383 68-69 383 Magnum / Right 2806900
383 68-69 383 Magnum / Left 2843992
383 70-71 B&C Body / Right 2899879
383 70-71 B&C Body / Left 2951865
383 70-71 C Body / Right 2899879
383 70-71 C Body / Left 2951216
383 70-71 C Body / Right 2899970
383 70-71 C Body / Left 2951861
413 59 Right 1739599
413 59 Left 2205536
413 61 300G / Right 2205830
413 61 300G / Left 1947434
413 61-64 Right 2205535
413 61-64 Left 2205536
413 62 Max Wedge / Right 2402334
413 62 Max Wedge / Left 2402336
413 63-64 300J & 300K / Right 2402781
413 63-64 30J & 300K / Left 2402782
413 65 Right 2205535
413 65 Left 2463107
426 63-64 Max Wedge / Right 2402334
426 63-64 Max Wedge / Left 2402336
426 Hemi 64-65 Hemi / Right 2465657
426 Hemi 64-65 Hemi / Left 2468658
426 64-65 Right 2205898
426 64-65 Left 2203262
440 66-68 Right 2532464
440 66-68 Left 2461307
440 67  440 Magnum / Right 2806900
440 67 440 Magnum / Left 2806974
440 68-69 440 Magnum / Right 2806900
440 68-69 440 Magnum / Left 2843992
440 70-71 C Body / Right 2899879
440 70-71 C Body / Left 2951216
440 70-71 B - C Body / Right 2899879
440 70-71 B - C Body / Left 2951865
440 70-71 C Body / Right 2899970
440 70-71 C Body / Left 2951861

 

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