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Old 01-14-2014, 02:25 PM   #24
DylanFRS
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Quote:
Originally Posted by arghx7 View Post
Yes.

It has AVCS on intake and exhaust cams. Basically, a hydraulic cam phaser moves the cam centerlines. Intake cam can be advanced from the most retarded position, and exhaust cam can be retarded from the most advanced position. This allows overlap if the cams are phased far enough.

Now, it depends on the grind of the cam. If the intake valve opens at 20 degrees ATDC intake, and exhaust closes at 10 degrees BTDC intake, you need over 30 degrees of intake cam advance to create overlap and backflow into the port.
So is the valve overlap messed with for higher RPMs? Because that would means these engines have variable valve timing and I would be surprised that it isn't making more power in the top end. Granted it wouldn't change profiles as vtec engines do.
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