Quote:
Originally Posted by 95cobra
can you explain, because im new to boost.
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Valve overlap, It's when the exhaust and intake valves are open at the same time(exhaust valve is closing and the intake valve is opening at the end of the exhaust stroke and the beginning of the intake stroke). This is done to help scavenge a cleaner intake charge into the cylinder, This is done for naturally aspirated applications which have to rely on atmospheric pressure to fill the cylinders. An application where boost is used doesn't need the increased amount of overlap because your intake tract is under a positive pressure, All overlap will do is allow fresh air to be blown out of the exhaust thus wasting potential power. The stock cam works good with boost and the savings can be applied to your stroker build, The stock cam with 1.7 rockers will give you .474 valve lift and a very tame idle. It makes for a real fun daily driver and has the stealth advantage, If you do go with an aftermarket cam find one with a minimal amount of valve overlap.