CAMSHAFTS -- WHAT? HOW? WHY?

By George Riehl

Reprinted from the 1979 Issue of the Chrysler 300 Club News Volume V Number III

It is the writer’s goal to show various differences of hemi engine versus hemi engine and wedge to wedge as far as performance is affected.

The 1955, 1956 and 1957 engines share the same camshafts, but then the 1957 uses a larger 2.00 intake valve versus the previous 1.94 valve. Without further discussion, the 1957 300C engine performs better. Raw cubic inch factor is also involved.

One exception exists with the 1956 300B engine. That is the 355 horsepower version. That was accomplished with an optional head that increased compression to 10.0 to 1 and torque was raised from 385 lbs. to 405 lbs.

The 1957 390 HP engine used a different camshaft than all others. There seems to be more than one variation of this engine camshaft ranging from the solid lifter type to an Iskendarian roller cam assembly. Then there is another unknown cam that is currently being degreed and checked on specifications. The variety of cams for 1957 was a result of Chrysler’s racing program.

Then in 1958, the hemi was offered with an electronic fuel injection unit that was of Bendix design. The standard 392 300 engine and the F. I. engine shared the same camshaft. The use of fuel injection would result in higher horsepower, 10 to be exact, with all other factors the same as the 380 HP engine except for exhaust manifold size.

In 1959 the 413 wedge appeared, and whether anyone wants to dispute it or not, with less performance than the previous 2 years of 300s. The camshaft design was changed greatly which resulted in engine deficiency. The table quite clearly shows the reason. Plus it (the engine) was not a well tested performance engine. This was due to less expensive block and head casting versus the higher cost hemi engine. Chrysler HAD to economize!

The 1960 and 1961 engines showed much more promise with the ram tuned engine. Much experimenting went into these engines and they seem to be the most unique in the world of automotive history. Rams actually do ram in fuel/air mixture to the cylinders and result in progressive compression ratio changes only in the fact of putting in more cubic inches of fuel/air mix into the cylinders than they were normally designed for. Not only that, but the runners on the tubes leading from the carbs to the heads of the intake valves created a pulsing action that would sonically and physically push the air into the combustion chambers. This also helped to “blow” out some of the burnt gases from the combustion chamber into the exhaust system.

The optional cam for the 1960 and 1961 413-400 HP engine was of different technical design because they used not hydraulic lifters, but used solid lifters with adjustable rockers. Hydraulic and solid lifter camshafts cannot be exchanged between their components. The grinding of the cam profile is quite different. The 400 HP cam is more radical than the standard cam by the then standards.

The 1962 413-380 HP engine went to solid lifter camshaft and was of better design than the 1959 version. But then again, the 1959 engine used a hydraulic camshaft. Also the 1962 engine used a smaller exhaust valve that reduced its efficiency slightly.

The 1963 and 1964 ram engine used the ram tubes of slightly different design. The inside partitions were made shorter than the 1960 and 1961 engines and the camshaft was again modified to “match” the ram tubes. These camshafts used solid lifters. Larger exhaust valves and “short” tubes teamed with camshaft design, resulted in one of, if not the best, the best performing 300 engines by far.

For the non-ram 1964 and 1965 413-360 HP engines, again the camshaft design was changed to match the single 4 bbl carb. This cam was also hydraulic and was a result of proven performance on the street with the 361, 383, and 426 wedge high-performance engines. This camshaft (design or grind) has powered many a Chrysler product engine from about 1959.

I have researched some “hot rod” of higher performance after market camshafts that may be used as a replacement for a worn out or broken camshaft for your 413 wedge engines. Remember that these cams were designed for higher compression and larger valved engines that were not of the ram manifold design. Technical involvements arise when going to a “bigger stick” in your engine and may cause other problems like valve to piston interference and too great a progressive compression ratio increase. Example – one might use the Crower 32914 cam in the 1959, 1960, 1961 standard 300 engine and also in the 1964, 1965 360 HP engines.

One side effect of this replacement cam would be a complete change of valve springs, spring height specification changes and, of course, a reduction in miles per gallon used. Also, all lifters would have to be new.

This chart is to be used for your reference only and the club does not authorize any non-stock camshaft for your use. But, in some cases, what else would one do if a camshaft was needed badly to get a 300 on the road? Our Technical Director, Gil Cunningham, is continually trying to locate the original manufacturers of the original camshafts and will keep us all posted. He has to date, located the original grinder of the 1963 and 1964 ram 390 HP engines. He is also following a lead on the 1957 (1955?, 1956?) cam manufacturer and will advise us as soon as it is verified.

Until original manufacturers are located and established that they still have the master cams, the option exists for the restorer to purchase a camshaft of recent manufacture that comes closest to the original 300 cam. But with the possibility of premium gasoline not being available in the very near future, the situation would exist that with the “performance” cams an engine on regular gas would start blowing holes in pistons, breaking rings, pounding out valves and valve seats and even to the point of damaging engine bearings.

The 300 engine may be a “brute” but it does have its limits, and if you want it to live a long and satisfying life, treat it as you would anything else of value. Treat it like a lady. Nothing is as pleasing as a good sound and pleasurable feelings. It is truly a love affair between man and his machines.

CAMSHAFT SPECIFICATIONS FOR 300 ENGINES

1955

1956

1957

1958

1959

1960

1961

1962

1963-64

1964-65

Std

Opt

Std

F I

Hyd

Solid

Hyd

Solid

Ram

Non-Ram

BTC0

35

35

35

20

32

32

20

20

25

20

25

22

18

24

ABC0

65

65

65

55

64

64

60

68

79

68

79

66

70

64

DURATION0

280

280

280

255

276

276

260

268

284

268

284

268

268

268

BBC0

65

65

65

60

73

73

58

60

74

60

74

62

66

64

ATC0

25

25

25

20

23

23

22

28

30

28

30

26

22

24

DURATION0

270

270

270

260

276

276

260

268

284

268

284

268

268

268

OVERLAP0

60

60

60

40

55

55

42

48

55

48

55

48

40

48

LIFT (intake)

.444

.444

.444

.455

.435

.435

.390

.430

.449

.430

.449

.444

.445

.430

LIFT (exh)

.435

.435

.435

.455

.442

.442

.390

.430

.454

.430

.454

.456

.452

.430

Intake Size

1.94

1.94

2.00

2.00

2.00

2.00

2.08

2.08

2.08

2.08

2.08

2.08

2.08

2.08

Exhaust Size

1.75

1.75

1.75

1.75

1.75

1.75

1.74

1.60

1.74

1.60

1.74

1.60

1.74

1.60

AFTERMARKET CAMS

HYDRAULIC LIFTER

(413-426-440)

SOLID LIFTER

(331-354-392)

Crower

Crower

Ramchargers

TRW

MoPar

Crane


Zimmer

Crane

RB CAMS

32100

32914

2910

TP140

P3690214

HT-284-2-NC


M-282-8-C

BTC0

34

18

32

TDC*

36

31

32

38

ABC0

66

66

68

38*

68

73

64

64

DURATION0

280

264

280

288

284

284

276

282

BBC0

74

66

68

44*

72

80

73

74

ATC0

26

18

32

6*

32

34

23

28

DURATION0

280

264

280

288

284

294

276

282

OVERLAP0

60

36

64

64

68

65

55

66

LIFT (intake)

.460

.450

.439

.444

.471

.430

.405

.443

LIFT (exh)

.460

.450

.439

.445

.474

.448

.4125

.443

* NOTE: @.050 cam lift

Jean-Yves Chouinard writes in 2016:
A conversation with George (around 2004 I think) revealed that he thought the best replacement cam for 60-61 long ram cars was cam "CS327 from Sealed Power". I have it in my F and in my G and just bought one for John's F convert we are restoring now. My engine shop says it is readily available, there was 90 in stock in Philadephia when they ordered mine!! My F engine was put on the dyno and came out with 495 ft/lb of torque at 2800 rpm, exact factory published numbers! John can attest to the good drivability of the car with that cam as he drove my F this Summer to go to the Macungie meet. You need a three key way crank gear and need to set it up at the 2 degree retard key, that will get you the correct valve timing required with ram manifolds. Looking at the engine shop invoice, it says: "Clevite 3pc. Timing set no. 9-3104" for the timing components. Hope this helps.

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