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The information on MP cams is calculated from the
published data in Chrysler manuals and catalogs. Data on other manufacturers' cams is from their catalogs or contributed from owners.
Duration @ .050” valve lift shown in the tables
is 85% (.850) of nominal for high-performance cams, and 77.7% (.777) of nominal for OEM
cams, per Chrysler. Duration @ .050” lift figures should only be used for
comparison between MP cams. In some cases, more (potentially) accurate
duration @ .050” figures appear as "Notes", with the source or author in
parentheses.
Cam timing figures listed are as installed on Chrysler-recommended centerlines. Cams may be installed in any position. Generally, advancing
or retarding the cam rotates all cam events simultaneously in one direction.
The event most affected by these changes is the intake valve closing point
ABDC ("After Bottom Dead Center"). Advancing the cam closes the intake
valve earlier, increasing cylinder pressure in the low to mid-range, and
reducing peak power. Retarding the cam closes the intake valve later, which
reduces low to mid-range power (and may reduce pinging), but potentially
improves peak power.
Lobe Separation Angle is fixed, and cannot be changed.
In mechanical-lifter (solid & roller) cams slight adjustment
can be made to Overlap & Total Duration by minor changes in valve lash. Non-standard lash
settings are recommended for test purposes. Crane suggests +.004" & -.008" (adjusted from manufacturer's suggested hot settings) as maximum limits for continuous use.
Increasing lash will increase cylinder pressure at low to mid-range speeds, close the intake valve sooner, and reduce Overlap & Total Duration. The effect is slightly similar to advancing the cam. Too much lash increases
wear on all components, lowers maximum RPM, and increases the possibility of breakage.
Reducing
lash will do the opposite: reduced cylinder pressure at low to mid-range speeds, later intake valve closure, and increased Overlap & Total Duration. The effect is slightly similar to retarding the cam. Too little
lash may result in a valve (especially an exhaust valve) not seating completely when the engine temperature
rises (such as a full-throttle 1/4 mile pass). |
Select Motor: |
Slant 6
170, 198, 225 |
LA Small Block
273, 318, 340, 360 |
B & RB Big Block
350, 361, 383, 400, 413, 426W, 440 |
Hemi
426 |
Slant 6: 170, 198, 225 |
244° Mechanical: P4120243 |
Intake Duration, Nominal |
244° |
Exhaust Duration, Nominal |
244° |
Intake Duration @ .050 |
190° |
Exhaust Duration @ .050” |
190° |
Intake Lobe Centerline |
106° ATDC |
Exhaust Lobe Centerline |
110°BTDC |
Lobe Separation Angle |
108° |
Overlap |
28° |
Intake Opens |
16° BTDC |
Exhaust Opens |
52° BBDC |
Intake Closes |
48° ABDC |
Exhaust Closes |
12° ATDC |
Intake Lift |
.436" |
Exhaust Lift |
.436" |
Note: as installed on 106° centerline per Chrysler |
268° Mechanical: P4529342 |
Intake Duration, Nominal |
268° |
Exhaust Duration, Nominal |
268° |
Intake Duration @ .050 |
208° |
Exhaust Duration @ .050” |
208° |
Intake Lobe Centerline |
104° ATDC |
Exhaust Lobe Centerline |
108°BTDC |
Lobe Separation Angle |
106° |
Overlap |
56° |
Intake Opens |
30° BTDC |
Exhaust Opens |
62° BBDC |
Intake Closes |
58° ABDC |
Exhaust Closes |
26° ATDC |
Intake Lift |
.460” |
Exhaust Lift |
.460” |
Note: as installed on 104° centerline per Chrysler |
276° Mechanical: P4286681 |
Intake Duration, Nominal |
276° |
Exhaust Duration, Nominal |
276° |
Intake Duration @ .050 |
214° |
Exhaust Duration @ .050” |
214° |
Intake Lobe Centerline |
104° ATDC |
Exhaust Lobe Centerline |
108°BTDC |
Lobe Separation Angle |
106° |
Overlap |
64° |
Intake Opens |
34° BTDC |
Exhaust Opens |
66° BBDC |
Intake Closes |
62° ABDC |
Exhaust Closes |
30° ATDC |
Intake Lift |
.490” |
Exhaust Lift |
.490” |
Note: as installed on 104° centerline per Chrysler |
284° Mechanical: P4529343 |
Intake Duration, Nominal |
284° |
Exhaust Duration, Nominal |
284° |
Intake Duration @ .050 |
221° |
Exhaust Duration @ .050” |
221° |
Intake Lobe Centerline |
102° ATDC |
Exhaust Lobe Centerline |
106°BTDC |
Lobe Separation Angle |
108° |
Overlap |
68° |
Intake Opens |
40° BTDC |
Exhaust Opens |
68° BBDC |
Intake Closes |
64° ABDC |
Exhaust Closes |
36° ATDC |
Intake Lift |
.528" |
Exhaust Lift |
.528" |
Note: as installed on 102° centerline per Chrysler |
LA Small Block: 273, 318, 340, 360 |
340 Stock Hydraulic: P4452782 |
Intake Duration, Nominal |
268° |
Exhaust Duration, Nominal |
276° |
Intake Duration @ .050” |
208° |
Exhaust Duration @ .050” |
214° |
Intake Lobe Centerline |
112° ATDC |
Exhaust Lobe Centerline |
116° BTDC |
Lobe Separation Angle |
114° |
Overlap |
44° |
Intake Opens |
22° BTDC |
Exhaust Opens |
74° BBDC |
Intake Closes |
66° ABDC |
Exhaust Closes |
22° ATDC |
Intake Lift |
.429" |
Exhaust Lift |
.444" |
Note: original standard-shift high-performance 340 4bbl.
cam |
Note: as installed on 112° centerline per Chrysler |
268°/272° Hydraulic: P4452761 |
Intake Duration, Nominal |
268° |
Exhaust Duration, Nominal |
272° |
Intake Duration @ .050” |
228° |
Exhaust Duration @ .050” |
231° |
Intake Lobe Centerline |
108° ATDC |
Exhaust Lobe Centerline |
112° BTDC |
Lobe Separation Angle |
110° |
Overlap |
50° |
Intake Opens |
26° BTDC |
Exhaust Opens |
68° BBDC |
Intake Closes |
62° ABDC |
Exhaust Closes |
24° ATDC |
Intake Lift |
.450” |
Exhaust Lift |
.455" |
Note: as installed on 108° centerline per Chrysler |
280° Hydraulic: P4452992 |
Intake Duration, Nominal |
280° |
Exhaust Duration, Nominal |
280° |
Intake Duration @ .050” |
238° |
Exhaust Duration @ .050” |
238° |
Intake Lobe Centerline |
106° ATDC |
Exhaust Lobe Centerline |
114° BTDC |
Lobe Separation Angle |
110° |
Overlap |
60° |
Intake Opens |
34° BTDC |
Exhaust Opens |
74° BBDC |
Intake Closes |
66° ABDC |
Exhaust Closes |
26° ATDC |
Intake Lift |
.474" |
Exhaust Lift |
.474" |
Note: as installed on 106° centerline per Chrysler |
284° Hydraulic: P4120231 |
Intake Duration, Nominal
|
284°
|
Exhaust Duration, Nominal
|
284°
|
Intake Duration @ .050” |
241° |
Exhaust Duration @ .050” |
241° |
Intake Lobe Centerline |
108° ATDC |
Exhaust Lobe Centerline |
108° BTDC |
Lobe Separation Angle |
108° |
Overlap |
68° |
Intake Opens |
34° BTDC |
Exhaust Opens |
70° BBDC |
Intake Closes |
70° ABDC |
Exhaust Closes |
34° ATDC |
Intake Lift |
.484" |
Exhaust Lift |
.484" |
Note: as installed on 108° centerline per Chrysler |
292° Hydraulic: P4120233 |
Intake Duration, Nominal |
292° |
Exhaust Duration, Nominal |
292° |
Intake Duration @ .050” |
248° |
Exhaust Duration @ .050” |
248° |
Intake Lobe Centerline |
108° ATDC |
Exhaust Lobe Centerline |
108° BTDC |
Lobe Separation Angle |
108° |
Overlap |
76° |
Intake Opens |
38° BTDC |
Exhaust Opens |
74° BBDC |
Intake Closes |
74° ABDC |
Exhaust Closes |
38° ATDC |
Intake Lift |
.508" |
Exhaust Lift |
.508" |
Note: 242° @ .050” (Herb McCandless) |
Note: as installed on 108° centerline per Chrysler |
276° Mechanical: P4529346 |
Intake Duration, Nominal |
276° |
Exhaust Duration, Nominal |
276° |
Intake Duration @ .050” |
235° |
Exhaust Duration @ .050” |
235° |
Intake Lobe Centerline |
110° ATDC |
Exhaust Lobe Centerline |
114° BTDC |
Lobe Separation Angle |
112° |
Overlap |
52° |
Intake Opens |
28° BTDC |
Exhaust Opens |
72° BBDC |
Intake Closes |
68° ABDC |
Exhaust Closes |
24° ATDC |
Intake Lift |
.490” |
Exhaust Lift |
.490” |
Note: as installed on 110° centerline per Chrysler |
284° Mechanical: P4120653 |
Intake Duration, Nominal |
284° |
Exhaust Duration, Nominal |
284° |
Intake Duration @ .050” |
241° |
Exhaust Duration @.050” |
241° |
Intake Lobe Centerline |
110° ATDC |
Exhaust Lobe Centerline |
114° BTDC |
Lobe Separation Angle |
112° |
Overlap |
60° |
Intake Opens |
32° BTDC |
Exhaust Opens |
76° BBDC |
Intake Closes |
72° ABDC |
Exhaust Closes |
28°ATDC |
Intake Lift |
.528" |
Exhaust Lift |
.528" |
Note: as installed on 110° centerline per Chrysler |
296° Mechanical: P4120655 |
Duration Intake Nominal |
296° |
Duration Exhaust Nominal |
296° |
Duration Intake @ .050” |
252° |
Duration Exhaust @ .050” |
252° |
Intake Lobe Centerline |
108° ATDC |
Exhaust Lobe Centerline |
112° BTDC |
Lobe Separation Angle |
110° |
Overlap |
76° |
Intake Opens |
40° BTDC |
Exhaust Opens |
80° BBDC |
Intake Closes |
76° ABDC |
Exhaust Closes |
36° ATDC |
Intake Lift |
.557" |
Exhaust Lift |
.557" |
Note: as installed on 108° centerline per Chrysler |
312° Mechanical: P4120657 |
Duration Intake Nominal |
312° |
Duration Exhaust Nominal |
312° |
Duration Intake @ .050” |
265° |
Duration Exhaust @ .050” |
265° |
Intake Lobe Centerline |
104° ATDC |
Exhaust Lobe Centerline |
108° BTDC |
Lobe Separation Angle |
106° |
Overlap |
100° |
Intake Opens |
52° BTDC |
Exhaust Opens |
84° BBDC |
Intake Closes |
80° ABDC |
Exhaust Closes |
48° ATDC |
Intake Lift |
.590” |
Exhaust Lift |
.590” |
Note: catalog data appears incorrect - shows impossible
figure (104°) for overlap |
Note: as installed on 104° centerline per Chrysler |
B & RB Big Block: 350, 361, 383, 400, 413, 426W, 440 |
440: Stock Hydraulic P4452783 |
Intake Duration, Nominal |
268° |
Exhaust Duration, Nominal |
284° |
Intake Duration @ .050” |
208° |
Exhaust Duration @ .050” |
221° |
Intake Lobe Centerline |
113° ATDC |
Exhaust Lobe Centerline |
117° BTDC |
Lobe Separation Angle |
115° |
Overlap |
46° |
Intake Opens |
21° BTDC |
Exhaust Opens |
79° BBDC |
Intake Closes |
67° ABDC |
Exhaust Closes |
25° ATDC |
Intake Lift |
.450” |
Exhaust Lift |
.458" |
Note: original 440, Commando, 383 Magnum etc. high-performance
cam |
Note: 208/220° @ .050” (R. Karkashian) |
Note: as installed on 113° centerline per Chrysler |
272° Hydraulic: P4286677 |
Intake Duration, Nominal |
272° |
Exhaust Duration, Nominal |
272° |
Intake Duration @ .050” |
231° |
Exhaust Duration @ .050” |
231° |
Intake Lobe Centerline |
110° ATDC |
Exhaust Lobe Centerline |
114° BTDC |
Lobe Separation Angle |
112° |
Overlap |
48° |
Intake Opens |
26° BTDC |
Exhaust Opens |
70° BBDC |
Intake Closes |
66° ABDC |
Exhaust Closes |
22° ATDC |
Intake Lift |
.455" |
Exhaust Lift |
.455" |
Note: 222° @ .050” (Brad H) |
Note: as installed on 110° centerline per Chrysler |
280° Hydraulic: P4452993 |
Intake Duration, Nominal |
280° |
Exhaust Duration, Nominal |
280° |
Intake Duration @ .050” |
238° |
Exhaust Duration @ .050” |
238° |
Intake Lobe Centerline |
106° ATDC |
Exhaust Lobe Centerline |
114° BTDC |
Lobe Separation Angle |
110° |
Overlap |
60° |
Intake Opens |
34° BTDC |
Exhaust Opens |
74° BBDC |
Intake Closes |
66° ABDC |
Exhaust Closes |
26° ATDC |
Intake Lift |
.474" |
Exhaust Lift |
.474" |
Note: as installed on 106° centerline per Chrysler |
284° Hydraulic: P4120235 |
Intake Duration, Nominal |
284° |
Exhaust Duration, Nominal |
284° |
Intake Duration @ .050” |
241° |
Exhaust Duration @ .050” |
241° |
Intake Lobe Centerline |
108° ATDC |
Exhaust Lobe Centerline |
108° BTDC |
Lobe Separation Angle |
108° |
Overlap |
68° |
Intake Opens |
34° BTDC |
Exhaust Opens |
70° BBDC |
Intake Closes |
70° ABDC |
Exhaust Closes |
34° ATDC |
Intake Lift |
.484" |
Exhaust Lift |
.484" |
Note: as installed on 108° centerline per Chrysler |
292° Hydraulic: P4120237 |
Intake Duration, Nominal |
292° |
Exhaust Duration, Nominal |
292° |
Intake Duration @ .050” |
248° |
Exhaust Duration @ .050” |
248° |
Intake Lobe Centerline |
108° ATDC |
Exhaust Lobe Centerline |
108° BTDC |
Lobe Separation Angle |
108° |
Overlap |
76° |
Intake Opens |
38° BTDC |
Exhaust Opens |
74° BBDC |
Intake Closes |
74° ABDC |
Exhaust Closes |
38° ATDC |
Intake Lift |
.509" |
Exhaust Lift |
.509" |
Note: 242° @ .050” (Herb McCandless) |
Note: as installed on 108° centerline per Chrysler |
284° Mechanical: P4120659 |
Intake Duration, Nominal |
284° |
Exhaust Duration, Nominal |
284° |
Intake Duration @ .050” |
241° |
Exhaust Duration @.050” |
241° |
Intake Lobe Centerline |
110° ATDC |
Exhaust Lobe Centerline |
114° BTDC |
Lobe Separation Angle |
112° |
Overlap |
60° |
Intake Opens |
32° BTDC |
Exhaust Opens |
76° BBDC |
Intake Closes |
72° ABDC |
Exhaust Closes |
28°ATDC |
Intake Lift |
.528" |
Exhaust Lift |
.528" |
Note: as installed on 110° centerline per Chrysler |
296° Mechanical: P4120661 |
Duration Intake Nominal |
296° |
Duration Exhaust Nominal |
296° |
Duration Intake @ .050” |
252° |
Duration Exhaust @ .050” |
252° |
Intake Lobe Centerline |
108° ATDC |
Exhaust Lobe Centerline |
112° BTDC |
Lobe Separation Angle |
110° |
Overlap |
76° |
Intake Opens |
40° BTDC |
Exhaust Opens |
80° BBDC |
Intake Closes |
76° ABDC |
Exhaust Closes |
36° ATDC |
Intake Lift |
.557" |
Exhaust Lift |
.557" |
Note: as installed on 108° centerline per Chrysler |
312° Mechanical: P4120663 |
Duration Intake Nominal |
312° |
Duration Exhaust Nominal |
312° |
Duration Intake @ .050” |
265° |
Duration Exhaust @ .050” |
265° |
Intake Lobe Centerline |
104° ATDC |
Exhaust Lobe Centerline |
108° BTDC |
Lobe Separation Angle |
106° |
Overlap |
100° |
Intake Opens |
52° BTDC |
Exhaust Opens |
84° BBDC |
Intake Closes |
80° ABDC |
Exhaust Closes |
48° ATDC |
Intake Lift |
.590” |
Exhaust Lift |
.590” |
Note: catalog data appears incorrect - shows impossible
figure (104°) for overlap |
Note: as installed on 104° centerline per Chrysler |
282° Mechanical: Competition Cams |
Duration Intake Nominal |
282° |
Duration Exhaust Nominal |
282° |
Duration Intake @ .050” |
255° |
Duration Exhaust @ .050” |
255° |
Intake Lobe Centerline |
108° ATDC |
Exhaust Lobe Centerline |
108° BTDC |
Lobe Separation Angle |
108° |
Overlap |
66° |
Intake Opens |
33° BTDC |
Exhaust Opens |
69° BBDC |
Intake Closes |
69° ABDC |
Exhaust Closes |
33° ATDC |
Intake Lift |
.582" |
Exhaust Lift |
.582" |
Note: data courtesy of rat roaster |
Hemi: 426 |
278° Hydraulic: P4349259 |
Intake Duration, Nominal |
278° |
Exhaust Duration, Nominal |
278° |
Intake Duration @ .050” |
236° |
Exhaust Duration @ .050” |
236° |
Intake Lobe Centerline |
104° ATDC |
Exhaust Lobe Centerline |
112° BTDC |
Lobe Separation Angle |
108° |
Overlap |
62° |
Intake Opens |
35° BTDC |
Exhaust Opens |
71° BBDC |
Intake Closes |
63° ABDC |
Exhaust Closes |
27° ATDC |
Intake Lift |
.495" |
Exhaust Lift |
.480” |
Note: 228° @ .050” (R. Karkashian) |
Note: as installed on 104° centerline per Chrysler |
292° Hydraulic: P4349257 |
Intake Duration, Nominal |
292° |
Exhaust Duration, Nominal |
292° |
Intake Duration @ .050” |
248° |
Exhaust Duration @ .050” |
248° |
Intake Lobe Centerline |
108° ATDC |
Exhaust Lobe Centerline |
108° BTDC |
Lobe Separation Angle |
108° |
Overlap |
76° |
Intake Opens |
38° BTDC |
Exhaust Opens |
74° BBDC |
Intake Closes |
74° ABDC |
Exhaust Closes |
38° ATDC |
Intake Lift |
.524" |
Exhaust Lift |
.507" |
Note: 242° @ .050” (Herb McCandless) |
Note: as installed on 108° centerline per Chrysler |
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