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chevyrestoguy · 04-24-2009, 05:03 PM

To keep the MAP sensor from going nuts, try to keep the duration under 218 deg @ .050, and go with at least a 112 lobe center (preferably 114). The map sensor is reading manifold pressure (vacuum), and when you start scooting the cam's duration higher, the vacuum signal gets degraded, and the map sensor tries to compensate by moving the idle up and down searching for the vacuum signal that falls within map sensor's factory pre-set range. If I recall, it has to be around 17-19 inches.

There's lots of reputable cam companies (Lunati, Comp, Edelbrock) that make cams specifically for this application. I wouldn't buy a parts store cam because it's a generic grind that will give you zero performance gains over stock. Unless that's what he wants, which is fine.

04-24-2009, 05:03 PM	#5
chevyrestoguy Registered User Join Date: Mar 2005 Location: apple valley, ca Posts: 2,670	Re: tbi cam options without computer problems To keep the MAP sensor from going nuts, try to keep the duration under 218 deg @ .050, and go with at least a 112 lobe center (preferably 114). The map sensor is reading manifold pressure (vacuum), and when you start scooting the cam's duration higher, the vacuum signal gets degraded, and the map sensor tries to compensate by moving the idle up and down searching for the vacuum signal that falls within map sensor's factory pre-set range. If I recall, it has to be around 17-19 inches. There's lots of reputable cam companies (Lunati, Comp, Edelbrock) that make cams specifically for this application. I wouldn't buy a parts store cam because it's a generic grind that will give you zero performance gains over stock. Unless that's what he wants, which is fine.