Flathead chamber design

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jed
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Re: Flathead chamber design

Post by jed »

Pete any experience with raiseing the intake seat and or lowering the exhaust seat. Do you find much reversion
On long duration camshafts? And if so how do you deal with it?
Where do you run your intake and exhaust center lines and your LSA??
Is a big part of the 14/1 compression by using a small bore and very long stroke?? Very long stroke.
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Re: Flathead chamber design

Post by Pete1 »

jed wrote: Sun Sep 29, 2019 12:42 pm Pete any experience with raiseing the intake seat and or lowering the exhaust seat. Do you find much reversion
On long duration camshafts? And if so how do you deal with it?

> No, on raising or lowering seats. It is something to fiddle with though.
I run reversion dams in the exhaust. With the intake stacks off there is some reversion at 2 to 3K rpm but we never run that way.
I don't usually run long duration cams. They don't work too well on circle tracks.

Where do you run your intake and exhaust center lines and your LSA??

> Depends on the cam but 110 to 111 LSA. On the 404A I have been running 3 deg. retarded on the cam. It seems to work better for slide jobs. More
power at the passing point.

Is a big part of the 14/1 compression by using a small bore and very long stroke?? Very long stroke.

> BIG bore and long stroke. More inches the better as long as the rules are met and that is usually only a problem at Bonneville.
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