About 30 years ago a guy in L.A., Jerry Branch, said that air flow QUALITY
was more important than quantity. And he proved it repeatedly.
Bryan
Jon.the.Wise wrote:
> But bigger is not always better. If you look at Mitsubishi's 4G63 head
> design, you'll see that the older heads had larger intake ports, but
> the newer heads with slightly smaller ports have a better angle into
> the chamber...
>
> What happens is that the larger ports can flow more air, but the air
> along the walls of the ports is moving MUCH slower than the air in the
> middle of the port, and then when it hits the absurd angle it must
> take to get into the chamber, that slows things down even more,
> whereas on the smaller ports, the air velocity stays more consistant
> throughout the entire airstream, and has a more gradual angle into the
> chamber...
>
> Unfortunately, that doesn't really prove a whole lot on it's own, but
> the theory is, you want to be able to size the ports so that they are
> just big enough to flow the air you want to flow, and still small
> enough to flow it with even velocity.
>
> It sounds like you were aware of this and with the timeframe just went
> for bigger, which *IS* better than too small ;o)
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