Characteristics of VVT-i and Forced Induction

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Characteristics of VVT-i and Forced Induction

Postby Adamal » Sun Apr 10, 2005 11:00 pm

I am wondering a bit about the relevence of combining VVT-i and any type of forced induction.

I was under the impression that the reason for VVT-i (Or VTEC, VVT, etc etc) was due to the density of air and the amount of air required for a better A/F ratio at certain RPM. IE As the engine revs higher, VVT-i adjusts the cam profile to allow air into the cylinder earlier so that more air and fuel can be sucked into the equation. As the pistons are moving at a faster rate, they can suck more air in quicker.

So what effect would forced induction have on this? Where air is not sucked into the engine, but forced. The cylinders are getting the air requirements and then some, so do they really need to open earlier to let more air in?

Who can shed light on this for me, and am I on the right track here?
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Re: Characteristics of VVT-i and Forced Induction

Postby matt dunn » Mon Apr 11, 2005 12:35 am

Adamal wrote:I am wondering a bit about the relevence of combining VVT-i and any type of forced induction.

I was under the impression that the reason for VVT-i (Or VTEC, VVT, etc etc) was due to the density of air and the amount of air required for a better A/F ratio at certain RPM. IE As the engine revs higher, VVT-i adjusts the cam profile to allow air into the cylinder earlier so that more air and fuel can be sucked into the equation. As the pistons are moving at a faster rate, they can suck more air in quicker.

So what effect would forced induction have on this? Where air is not sucked into the engine, but forced. The cylinders are getting the air requirements and then some, so do they really need to open earlier to let more air in?

Who can shed light on this for me, and am I on the right track here?


I thought that VVT gives you the advantage of having more aggressive camshafts in your car without sacrificing the lower end of the rev range's performance.

How well it will work with boost will depend on the boost level and the camshaft profile wont it?

Matt
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Discussion - viewtopic.php?t=59751
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