Stock cam specs (as measured by Crower):

• Type : Hydraulic roller, assembled (hollow core with pressed on lobes)
• Duration : 196� intake / 196� exhaust (@ 0.050" lift)
• Lift @lobe : 0.273"
• with 1.6 roller rockers : 0.437"
• Lobe Seperation Angle : 112�

Stock cam specs (from www.napaonline.com)
*changed the lift for our stock 1.6:1 rockers

• Cam Lift (Exhaust):.272"
• Cam Lift (Intake):.272"
• Cam Timing at .050" Lobe Lift (Exhaust Close):12 Deg BTC
• Cam Timing at .050" Lobe Lift (Exhaust Open):32 Deg ABC
• Cam Timing at .050" Lobe Lift (Intake Close):29 Deg BBC
• Cam Timing at .050" Lobe Lift (Intake Open):15 Deg ATC
• Degrees Overlap:39 Deg
• Duration at .050" Lobe Lift (Exhaust):197 Deg
• Duration at .050" Lobe Lift (Intake):197 Deg
• Lobe Centerline (Exhaust):111 Deg
• Lobe Centerline (Intake):113 Deg
• Valve Lash (Exhaust):Hyd.
• Valve Lash (Intake):Hyd.
• Valve Lift (Exhaust):.430"
• Valve Lift (Intake):.430"

The lobe profile never changed for the Gen 3 engines, but there were changes made between years on the cam trigger. Why GM did this, we will never know. But from what we know from experience, the signal created by the cam position sensor (and thus sent to the PCM) is the same for all of the designs, so it is best to match the cam position sensor to the cam trigger of your particular cam.

1994-1999 : cam sync ring was a "missing tooth" design, requiring cam position sensor AC Delco PN 213-294
2000-2002 : cam sync ring was a "single tooth" design, requiring cam position sensor AC Delco PN 213-937
2003-present : cam sync ring is a 50/50 pattern of raised and lowered semi circles, requiring cam position sensor AC Delco PN 213-1533

(L to R) : 03-Present, 00-02, 94-99

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