The B Engines: 350, 361, 383, and 400

361 and 413 engines

Mopar B engine evolution (history): 350 to 400

361 wedge

How do you identify these engines? On the passenger side of the block, underneath the distributor, is a bit of smooth steel which has a number code stamped in it. The first line has a letter for the year (D = 1968) and the three digits for displacement (e.g. 440). The date — month and day — are on a line below, sometimes with an HP denoting High Performance. If you don’t find the “tag,” try just to the right of the distributor, where it sits on RB engines.

The B series engines were the first to be designed by the new corporate engineering department, which took over engine design from the divisions to end the complexity of having so many variations of the same basic package.

The department was faced with the question of whether to go with the heavy, expensive Hemi chambers, with the polyspherical heads, or with the wedge-shaped chambers used by most other automakers. In the end, they decided the cost and complexity of the Hemi was not called for, and discovered that the poly heads had little advantage over the wedge shape, and went with the wedge. The early B engines had five main bearings and hydraulic lifters.

The 'B' series wedge engine was introduced in 1958 with 350 and 361 cubic inch versions; the 361 would last until the end of the series, albeit for trucks only. In its early years, the 265-horsepower 361 was optional on many vehicles, and standard on, among others, the Dodge 880.

The new engine had a single rocker shaft, and stamped steel rocker arms; compared to the corporation’s first V8 engines, it was light, simple, and cheap to build, yet still tough and sturdy.

SonoRamic Commando

It took several years and considerable experimentation for the new engine to establish a reputation, partly because it replaced a successful series of hemispherical head ("early Hemi") engines. Still, it was created from the start to handle increasing amounts of power, with drop-forged steel connecting rods and a forged crankshaft along with a very deep-skirt block. Maintenance and repair were eased by the external oil pump, dry intake, and front-mounted distributor, along with an easily changed water pump.

Block Bore Stroke CID Block Bore Stroke CID
Low Block 4.06 3.38 350 High Block 4.18" 3.75" 413
  4.12" 3.38" 361   4.25" 3.75" 426
  4.25" 3.38" 383   4.32" 3.75" 440
  4.34" 3.38" 400   4.03 3.75 383

super red ramThe 350 was classified as a big block engine; all parts except for the pistons and water pump appear to be fully compatible with the 383. Plymouth versions were originally called Sonoramic Commando; Dodge versions, Super Red Ram and D-500; DeSoto versions, TurboFlash. The Plymouth version of the 350 was called the Golden Commando, and had 305 hp; the DeSoto version, Turboflash, produced up to 295 hp; and the Dodge version, called the D-500, went up to 320 hp. The 361 was essentially a bored 350.

Both the 350 and 361 had a fuel injected version in 1958 only. Very few of the "fuelies" were made, and only a handful - at most - remain since most were brought back to the dealer to get carburetors fitted.

Even though the 1958 engines were relatively tame, they were ready for more, with relatively large ports (1.95” intake, 1.60” exhaust) and engineered-in growth capability. After a single year, the 350 and 361 were greeted by the RB-type 413, a raised-deck version of the same engine. At that point, the 350 was dropped.

361 crankshaft

In 1959, the 361 was bored out, creating the modal Mopar performance engine for the next decade: the 383. The big bore allowed for larger (2.08”) intake valves, and the relatively short stroke helped it to be a free-revving engine as well as a free-breathing one. Pushing out a maximum of 330 horsepower (gross) and 460 lb-ft of torque in 1960, the 383 trumped the 392 Hemi, which had never beaten 435 lb-ft. The 1960 383 engines boasted the same basic ram induction system as the Chrysler 300F’s 413 RB engines (named SonoRamic Commando when sold in Plymouth form).

Dodge V8s
D500 (1) D500 (2) Ram-Fire Red Ram Super
Red Ram
Cubic Inches 361 383 383 318 361 318
Bore x Stroke 4.12 x 3.38 4.25 x 3.38 4.25 x 3.38 3.91 x 3.31 4.12 x 3.38 3.91 x 3.31
Compression 10:1 9:1 10:1 9:1 10:1 8.25:1
Carburetor Dual 4-barrel 4-barrel 2-barrel 2-barrel 2-barrel
Gross hp

310 @ 4,800 330 @ 4,800 325 @ 4,600 230 @ 4,400 295 @ 4,600 200@ 3,900
Max torque

435 @ 2,800 460 @ 2,800 425 @ 2,800 340 @ 2,400 390 @ 2,400 286 @ 2,400

Richard Bowman noted that the 361 DeSoto Turboflash version of the B engine went from a 10:1 compression ratio in 1960 to a 9:1 compression ratio in 1961, without losing performance (it had 265 gross hp in 1961) because the compression change was accompanied by enlarged intake valves. This let owners use regular gas instead of premium.

turboflash 361 v8

Carburetion in 1961 was supplied by a two barrel Stromberg model WWC carburetor (model number 3-188). This carburetor had a rubber-tipped needle valve in the float bowl, making the unit less sensitive to flooding by enveloping small dirt particles and still maintaining a good seal; and it had a two-stage set-up jet for better fuel flow at cruising speeds. In 1960, a carburetor with a three-stage metering rod was used.

3-stage metering rod

361 carburetors1961 was the first year for the closed crankcase ventilation system used on all cars sold in California, designed to painlessly reduce smog. A flexible tube connected a valve and a specially calibrated carburetor; the carburetor had a fitting just below the throttle blades into which the crankcase vapors were drawn by suction. From here they were drawn into the intake manifold for burning, leaving fewer vapors to be discharged into the atmosphere. All cars now use this system.

1968 dodge engines

In 1966, the truck 361 was rated at 186 horsepower at 4,000 rpm and included induction-hardened crankshaft journals, trimetal main and connecting rod bearings, hydraulic valve lifters, sodium-filled exhaust valves with Roto-Caps, and a chrome-alloy cast-iron block. Despite the illustration, engines were not chrome-plated and fully painted.

The B-engine performance story

The performance story of the 'B' engine begins with the introduction of the Dodge 383 cubic inch B-engine, coded as D500, with 330 hp using a cross-ram induction manifold with twin four-barrel Carter carburetors. This engine was both a factory and dealer option, for all models.

383 overhead view

super red ram

Chrylser Engines 1922-1998 Willem WeertmanThe B series 383 joined the lineup in 1962. This workhorse engine was rated at 343 hp with two four-barrel carburetors, making it the most powerful B series 383 ever produced. (Jerry Gulino pointed out that a 345 hp 383 engine had been used in 1959, in the Super D-500 2x4s. The Ultimate Guide to V8 Engines says that the 383 went up to 350 hp in 1959).

The A-864 hemi was introduced in '64 in the "light weight" Plymouth and Dodge models as a race only package, to be replaced by the A-990 hemi in 1965 (also as a race only engine).

d500 engine

The performance aspects of the 'B' and 'RB' engines faded from 1972 on, though not as suddenly as casual observers may expect, because net horsepower ratings were adopted in 1972 as well. This resulted in a substantial drop in rated horsepower as the effects of using an air cleaner, water pump, alternator, muffler, and other “accessories” were included. The company did provide both gross and net numbers for some engines in 1971, providing some perspective. The measurement difference was responsible for a “drop” of 50-65 horsepower.

1972 Carburetor Net Horsepower Torque (lb-ft)
360 4-barrel. 175 @ 4,000 285 @ 2,400
4002-barrel190@ 3600 305 @ 3200
4404-bbl 225 @ 4,800345 @ 3200
440 4-bbl dual snorkel230 @ 4,400355 @ 2,800
4404-bbl dual exhaust245 @ 4,400360 @ 3,200
440Hi-Po280 @ 4,800375 @ 3,200
440Cold Air Pak290 @ 4,800380 @ 3,200
4403-two barrel330 @ 4,800410 @ 3,600

There were some real drops in power in 1972 as compression was dropped to reduce emissions, a cheap way to meet new pollution standards. There was also a new B engine, the largest ever made, a large (4.34) bore version of the 383 B engine with many internal parts differences. According to Rick Ehrenberg of Mopar Action, the original idea behind the 400 cubic inch V8 was to standardize all B and RB engines with a 4.32” bore; that would have resulted in a 396 engine, and, according to Mr. Ehrenberg, the marketing people felt an even 400 would sell better.

Starting in 1973, exhaust-valve seats were induction-hardened to allow use of lead-free fuels. In the hardening process, seats reach a temperature of 1700°F and are then allowed to air-cool. This hardened the valve­seat surfaces to a depth of .05" to .08" which gives them greater resistance to wear than unhardened seats. Maintenance was eased and reliability increased in the same year (1973) by the addition of the Chrysler electronic ignition system, which had been launched in some 1972 cars.

From 1973 to 1978, emissions equipment continued to become more complex, as engineers worked minor miracles to get carburetors to work more efficiently under all conditions. Fuel injectors were suggested, according to Allpar interviews, but rejected due to cost (which was most likely far less than the cost of the extra warranty work and lost customers). The 1975 addition of Electronic Lean Burn, the world’s first computerized spark advance system, helped somewhat. Cast crankshafts started to replace the forged crankshafts of prior years.

torque curveIn 1978, the 400-cubic-inch V-8 engines gained dual concentric throttle return springs in addition to a torsion throttle spring.

The heat valve in the right exhaust manifold diverts hot gases to the floor of the intake manifold which helps to vaporize the fuel mixture when the engine is cold. This results in faster warm-up and improves driveability after a cold start. During warm-up, a thermostatic spring allows the heat valve to open to the exhaust pipe-so gas flow through the intake manifold crossover passage is decreased.

All 1978 Chrysler V-8 engines had an adaptor to receive a magnetic probe for timing the ignition magnetically. The adaptor is a little steel sleeve attached to the bracket that has the traditional timing marks-you can still set the ignition with a timing light. However, ignition timing was set magnetically on all engines at the factory for accuracy. The magnetic timing adaptor will also help those who have the equipment to time Lean-Burn engines magnetically.

The performance aspects of the 'B' and 'RB' engines faded from 1972 on until the last one was produced in August 1978, ending the history of Chrysler Corporation big-block engines. The engines were, by then, selling slowly enough that the last vehicle built with one was made in 1979 — a pickup truck.

400 V8

1977 440 V8 engine

Mopar B and RB engine parts

361 V8Over 3 million 383 engines were produced through 1971, and over 3/4 of a million 440 engines have been produced which makes parts readily available. The 'B' engine and can be identified by the cubic inches stamped on the right side of the block deck adjacent to the distributor. The RB engine has the engine size stamped on a pad at the left front of the engine adjacent to the front tappet rail. All 'B' and 'RB' distributors are at the right front of the engine. Parts replacement information (such as undersize crankshaft) is located next to the engine size.

'B' series wedge engines have virtually complete parts interchangeability with few exceptions. Gary Howell noted that the RB required a wider intake manifold, and that the B engines all used a 3.38 stroke crank.

The last year of the 361 in cars was 1966, but it lasted at least until 1972 in trucks, according to Jim Smith, who said his father had a Dodge bulk feed truck with that engine. A 1968 school-bus brochure which lists the 361 as the largest engine, pumping out 186 horsepower with a two-barrel carburetor. “shadowrider” wrote: “I worked on the V8 assembly line at Trenton engine from 1976-78 and we were still assembling the 361 (and 413) along with the 400 and 440s until 1977 when this line was shut down. These engines (361 and 413) were going into heavy duty trucks and Winabagos.”

Chrysler wrote about the 400: “The 4-barrel carburetor, large intake and exhaust valve ports and large diameter exhaust pipe give this engine the excellent breathing necessary for good engine performance. This means responsive acceleration at cruising and highway passing speeds. A deep-skirt engine block and rugged cast ductile iron crankshaft contribute to the durability of this engine. Main bearings are durable aluminum-on-steel construction.”

The two 383 engines (by Curtis Redgap)

lynn townsendThe 383 "RB" (Chrysler) had its head deck raised, and was stroked to the famous (or infamous) 3.75 inches that covered the RB 383, the 413, the 426, and with the thin wall casting techniques, the 440. It had the same stroke as the 426 "HEMI."

In the "RB" family, the major difference is the bore size. The 383 was a 4.03 inch bore. The 413 saw a 4.18 inch hole which was an easy leap to the NASCAR limit of 426 cubic inches by boring the block to a 4.25 inch diameter. At the time, that was about the limit for this block.

In 1966, thanks to development of precision thin wall casting techniques used to make the 1964 small 273 ci V-8, this same RB could be pushed out to 4.32 inches which gave us the 440.

While Chrysler at the time had its eyes on the racing development of the 413-426 family, it wasn't asleep. Lynn Townsend saw the need for a small engine for the "small car" lines at Chrysler. It took two years, which isn't too shabby a development time. The 273 was a great little V-8, with lots of potential that was only touched by engineers.

361 V8 engine

Other articles

Specifications for 1958 Dodge models Red Ram
(325 Poly)
Super Red Ram
(350/361 B engine)
Type 90 deg V8 90 deg V8
Valve Arrangement In Head Single Rocker Shaft
Bore 3.69" 4.0625" (350)
4.125" (361)
Stroke 3.80" 3.375"
Piston Displacement (cu. inch) 325.0 Cu 350 and 361
Taxable Horsepower (AMA) 43.9 52.81 (350)
Compression Ratio 8.5 to 1 10 to 1
Compression Pressure (minimum 150 rpm,
plugs removed, wide open throttle)
90 (min) - 155 (max) 150 (min) - 180 (max)
Maximum Variation Between Cylinders 15 lbs 25 lbs
Firing order 1-8-4-3-6-5-7-2 1-8-4-3-6-5-7-2
Cylinder numbering (from drivers seat,
front to rear)
1-3-5-7 left, 2-4-6-8 right
Engine Lubrication: Pump Type Rotary Full Pressure
Camshaft drive
Rotary Full Pressure
Camshaft drive
Crankcase Capacity (qts) 5 4
Minimum Pump Pressure at 500 rpm 15 psi 15 psi
Operating Pressure at 40 to 50 mph 1500 RPM 50-65 lbs 45-70 lbs
Oil Filter Type Shunt; replaceable
Full Flow; replace
Cylinder Bore (std) 3.6875-3.6895" 4.0625-4.0845"
Cylinder Bore Out-of Round
(max. before reconditioning)
.005" .005"
Cylinder Bore taper (max. before reconditioning) .020" .010"
Max allowable over bore .060" .040"
Camshaft Drive Chain Chain
End play .002-.006" 002-.006"
Max allowable .010" .010"
Radial clearance .001-.003" .001-.003"
Max allowable .010" .005"
Camshaft chain
Number of links 68 50
Pitch .375" .50"
Width 1 1/8" .88"
Camshaft Journals Diameter and Length - #1 1.998-1.99 x 7/8"
#2 1.982-1.983 x 3/4"
#3 1.967-1.968 x 3/4"
#4 1.951-1.952 x 3/4"
#5 1.4355-1.4365 x 15/16"
Crankshaft Type Fully Counterbalanced
Bearings Steel Backed Babbitt
Thrust taken by No.3 main bearing
End Play .002-.007"
Max allowable .010"
Radial Clearance .0005-.0015"
Max allowable .0025"
Finish at rear Oil Seal Surface Diagonal Knurling
Main bearing Size Diameter and length No.1 2.50 x.73"
No.2 2.50 x.73"
No.3 2.50 x.72"
No.4 2.50 x.73"
No.5 2.50 x 1.19"
Main bearing Journals Diameter 2.5 2.625
Max Allowable Out of round .001" .001"
Max Allowable Taper .001" .001"
Center Bearing Run-Out
(total indicator reading)
when supported at front and rear main bearing
.002" .002"
Crankpin Journals
Diameter 2.2495-2.2505" 2.2495-2.2505"
Max Allowable Out of round .001" .001"
Max Allowable Taper .001" .001"
Connecting Rods
Length (center to center) 6.62 6.358
Weight (less bearing shell) 22.5 28.6
Bearings Steel Backed Babbitt Steel Backed Babbitt
Diameter and Length 2 1/4 x 13 /16" 2.375 x .927"
Clearance .0005-.0015" .0002-.0022"
Max allowable .0025" .0025"
Side Clearance .009-.017" .009-.017"
Connecting Rod Bushing Type Steel Backed Bronze none
Diameter and Length 1.110-1.125-.9217-.9220 ____
Pistons Conformatic with Steel Strut /
Horizontal Slot with Steel Band
Material Aluminium alloy tin coated
Land Clearance (in Bore) .027-.033" .042-.047"
Clearance (top of Skirt) .0005-.0015" .0005-.0015"
Weight (Standard through all oversize) 18.6 oz 705 gram
Ring Groove Width (upper) .032" .032"
(intermediate) .0790-.0800" .0790-.0800"
(lower) .1875-.1890" .1875-.1890"
Valves (intake)
Head Diameter 1.84" 1.95"
Length (overall) 4.31" 4.81"
Stem Diameter .37" .37"
Stem to Guide Clearance .002" .002"
Max. allowable .004" .004"
Face angle 45 deg 45 deg
Valves (Exhaust)
Head Diameter 1.47" 1.60"
Length (overall) 4.31" 4.81"
Stem Diameter .37" .37"
Stem to Guide Clearance .003" .003"
Max. allowable .006" .006"
Face angle 45 deg 45 deg
Valve guides
Type Cast in Head Cast in head
Size .374" .374"
Valve Springs
Pressure when compressed (Valve Closed) 1.69"-72 lbs 1.86"-75 to 85 lbs
Pressure when compressed (Valve Open) 1.31"-166lbs 1.47"-173 to 187 lbs
Valve spring installed height
(spring seat to retainer)
1 5/8 - 1 11/16" 1 55/64"

super red ram engine

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