October 5th 7 pm Darin Morgan

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I thought they could support more rpm cause of cross flow, from intake to exhaust.
That is part of it as well.

Compare the 2 extremes here. Look at a wedge head chamber around the entire perimeter of the intake valve and compare it to the chamber around the perimeter of the hemi intake valve. In the chamber the hemi makes a nice 'cone' around the valve. This allows the air to get around the valve and into the chamber very smoothly and very evenly around all sides of the valve. This allows for the near ideal 'pressure recovery' that Darin talks so much about. A wedge head has many different angles around the valve, has shrouding on the cyl wall side and has a problematic short turn. The air flow around the perimeter of a wedge head valve is far from even. Thus more cfm/sq in of valve area for the hemi and the capability of higher rpm.

The canted/rotated valve arrangement takes advantage of much of the high flow characteristics of the hemi without the need for a huge piston dome and large (surface area) combustion chamber.
 
That’s one of the reasons I use a 4.015 bore adapter for testing even with 2.08 valves. In my head I feel with shortturn shaping you can dictate the direction that most of the airflow is going. Probing the runner for airspeed can back this theory up. Think 3D and check each runner from every angle.
Near the end of the video he shows the narrow quench pad that he left on the shrouded side of the intake valve. He left it there to keep velocity up in that area instead of unshrouding the valve and increasing flow (which he said also decreased the velocity in that area of the valve). Fascinating.
 
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I know one thing he’s not a lover of alcohol unless he’s changed his thinking. He told us he could make more horsepower with gas and I Dont even think Q16 was available yet.
 
I know one thing he’s not a lover of alcohol unless he’s changed his thinking. He told us he could make more horsepower with gas and I Dont even think Q16 was available yet.


And he’s not wrong. NA I can make more power with gas than alcohol.

That’s why I switched back to gas before I stopped racing.
 
I wish buddy would stop interrupting Darin, he's going off on some interesting tangents but gets shutdown with nonrelated questions/comments.
 
I wish buddy would stop interrupting Darin, he's going off on some interesting tangents but gets shutdown with nonrelated questions/comments.
I really struggle with watching Tim Halsted's videos for that very reason, you're not alone
 
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