Thread: Building a new motor

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If I were going to buy a cam and lifters for your motor, using aluminum heads, (at 9.5:1 SCR), it would be a Howards CL110235-12 Retrofit Roller...
Intake opens (-1.5) BTDC
Intake closes 34.5 ABDC
Exhaust opens 44.5 BBDC
Exhaust closes (-7.5) ATDC
Intake centerline 108
Exhaust centerline 116
Lobe separation angle 112
Howards Cams Retro-Fit Hydraulic Roller Camshaft and Lifter Kits CL110235-12 - Free Shipping on Orders Over $99 at Summit Racing

If you wanted to take your chances with a flat tappet hydraulic cam and lifters and iron heads, it would be a Crane 2050 (114142) cam and lifters. This cam uses considerably more exhaust duration than intake duration to help evacuate the cylinders on iron heads with less efficient runners and still keep the intake closing point in concert with the static compression ratio to make good cylinder pressure. You can see this by looking at the exhaust open numbers, this cam begins blowing down the cylinder earlier than the Howards roller cam does.
Intake opens 1.0 BTDC
Intake closes 35 ABDC
Exhaust opens 51 BBDC
Exhaust closes (-3) ATDC
Lobe separation angle 112
Crane CompuCam Cam and Lifter Kits 114142 - Free Shipping on Orders Over $99 at Summit Racing

You can pick any cam you want to for the motor, just stay around 35 degrees or a little less on the intake closing point with the SCR at 9.5:1.

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