CAM LOBE PROFILE CATALOG - Crane Cams Australia

MECHANICAL ROLLER PROFILES
PROFILE CODE
DUR. AT .050”/
LOBE LIFT
ADVERTISED DUR.
AT TAPPET LIFT
DEG. IN.
DUR. AT
.200”
TAPPET LIFT
MECHANICAL ROLLER PROFILES
TAPPET LIFT AT
TOP DEAD CENTER
104 DEG.
INTAKE
114 DEG.
EXHAUST
GROSS VALVE LIFT WITH ZERO LASH AT
THEORETICAL ROCKER RATIO SHOWN
cranecams.com | 866.388.5120
DESIGN
LOBE SIZE
CODE
1.50 1.60 1.70 1.76 SEE PAGE 3
471 Continued from previous page.
R-286/471 318 .0200 202 .183 .145 .707 .754 .801 .829 B C G
R-294/471 328 .0200 207 .194 .160 .707 .754 .801 .829 B H
4168 IR
4168 IR roller series created for oval track applications with aggressive inverted flank areas for small
block Chevrolet size lobes. Recommended lash is .012”. Not recommended for high RPM applications.
IR-248/410 284 .0160 169 .114 .082 .615 .656 .697 .722 B
IR-252/4134 288 .0160 173 .122 .088 .620 .661 .703 .728 B
IR-256/4168 292 .0160 176 .131 .094 .625 .667 .709 .734 B
IR-260/4168 296 .0160 180 .139 .101 .625 .667 .709 .734 B
IR-264/4168 300 .0160 184 .148 .108 .625 .667 .709 .734 B
IR-268/4168 304 .0160 188 .157 .116 .625 .667 .709 .734 B
IR-272/4168 308 .0160 191 .165 .123 .625 .667 .709 .734 B
IR-276/4168 312 .0160 195 .173 .131 .625 .667 .709 .734 B
IR-280/4168 316 .0160 199 .181 .139 .625 .667 .709 .734 B
4334 IR
4334 IR roller series created from the Cam Dynamics series of masters for
oval track applications with aggressive inverted flank areas. Recommended
lash is .012”. Not recommended for high RPM applications.
IR-254/4334 278 .0245 179 .133 .093 .650 .693 .737 .763 B
IR-258/4334 282 .0245 182 .142 .100 .650 .693 .737 .763 B
IR-262/4334 286 .0245 186 .150 .107 .650 .693 .737 .763 B
IR-266/4334 290 .0245 190 .160 .115 .650 .693 .737 .763 B
IR-270/4334 294 .0245 193 .168 .122 .650 .693 .737 .763 B
IR-274/4334 298 .0245 197 .176 .130 .650 .693 .737 .763 B
IR-278/4334 292 .0245 201 .185 .139 .650 .693 .737 .763 B
422
422 roller series created for oval track and drag racing that gives a .650”+ net valve lift
when used with a 1.6:1 or higher rocker ratio. Sized on a .950” diameter base circle for
Buick and long stroke (small base circle) Chevrolet with a .012” recommended lash.
R-262/422 290 .0200 183 .143 .106 .633 .675 .714 .743 A
R-266/422 294 .0200 186 .151 .121 .633 .675 .714 .743 A
4403
4403 roller series created as a step up from the 420 series with improved high-speed dynamics,
popular oval track intake lobes. Use with up to a 1.8 rocker ratio. Recommended lash is
.020" intake and .022" exhaust, allowing for a tight cold setting on aluminum engines.
R-260/4403 290 .0200 182 .140 .102 .660 .704 .785 .775 B F
R-262/4403 292 .0200 184 .144 .105 .660 .704 .785 .775 B C F
R-264/4403 294 .0200 186 .148 .109 .660 .704 .785 .775 B C F
R-266/4403 296 .0200 188 .153 .113 .660 .704 .785 .775 B C F
R-268/4403 298 .0200 190 .157 .117 .660 .704 .785 .775 B C F
R-270/4403 300 .0200 192 .161 .121 .660 .704 .785 .775 B C
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