Reply to "4V Heads"

sigMember

Mikael,
It is not for my car. I'm very happy with my A3 heads. It is a friend in Toulouse that has 4V heads and believes that smaller ports (something in between 2V and 4V) increases air velocity and provides better cylinder filling. I was sceptic about his approach but then I saw recently the Engine Masters episode 28 (YouTube) where they measured the power difference between heads of different port sizes. Surprisingly, it was not that the big size ports loose torque at low rpm and neither does the big size ports develop most power. I'm not sure whether this conclusion is valid for all engines, however, this are interesting results.
SIG

1/16/188:38 AM

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