Hi,
I start "thinking" as a driver of a big 4x4, which needs torque at low revs and needn´t be able to be chased on laps.
If I changed the camshaft for one which promises more power and torque then I will get one, whith a longer duration. So the cam lobe will be longer - and the valve been opened earlier and closed later. That in turn gives the cylinder more time to shift the gases (mixture/exhaust) - which is a benefit at high revs, when the time for each cylce is relatively less.
But why does this cam affect the idle badly. Why will the idle be lumpy, the idle MAP higher and why the fuel consumption increased (*) ??
(*) is that just because of a greater overlap of inlet/exhaust valves, "erratically" shifting more fresh mixture into the exhaust ? And/or is it due to more power being developed at those higehr revs which certainly imply more fuel being used ?
why is a sports-camshaft bad for idle ?
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Read the manual to see if your question is answered there before posting. Many users will not reply if the answer is already available in the manual.
If your question is about troubleshooting, configuration, or tuning, you MUST include your processor type (MS-I or MS-II) and code version in your post. If your question is about PCB assembly or modifications, you must also include the main board version number (1.01, 2.2 or 3.0).
If you have questions about MS1/Extra or MS2/Extra code configuration or tuning, please post them at www.msextra.com Such questions posted here will be moved to: a temporary MSextra sub-forum, where they will be removed after 7 days
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why is a sports-camshaft bad for idle ?
Range Rover Classic - 4.2V8, c/r 8.9:1, standard - EDIS - KnockSense - Innovate LC-1 - MS-2 (B&G - code 2.883j)(continuous baro)(dualEGO but only one sond used)(stepper IAC)
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Matt Cramer
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Re: why is a sports-camshaft bad for idle ?
Yep, it's the overlap. It can blow the intake charge out the exhaust valve at low RPM. You'd want a cam ground for 4 x 4 applications.
