Big Block Mopar valve offset

[Ken_Parkman]

Doing some research on big block Mopar heads for a project I am working on. Does anyone have a head blueprint they are willing to share? And/or know the distance the valve pierce point is from the bore centreline? Just looking and visually the valves are way low, maybe 1/4" inch? How far did the valves have to be moved to centre them on some of the Mopar race heads?

[Erland Cox]

When I raced with Mopar engines I used to move the heads up 0,1 inch.
That was all that was possible but it made the heads flow what they did at 0,6" at 0,5" so it really helps.
I have no blueprint though.

Erland

[Walter R. Malik]

Doing some research on big block Mopar heads for a project I am working on. Does anyone have a head blueprint they are willing to share? And/or know the distance the valve pierce point is from the bore centreline? Just looking and visually the valves are way low, maybe 1/4" inch? How far did the valves have to be moved to centre them on some of the Mopar race heads?

Intake = 1.15" from bore centerline
Exhaust = .93" from bore centerline
Horizontal centerline for both valves = .3146"toward the exhaust side from bore centerline

[Ken_Parkman]

Thanks guys!

Wow, over 5/16" from the centreline!

[DCal]

Doing some research on big block Mopar heads for a project I am working on. Does anyone have a head blueprint they are willing to share? And/or know the distance the valve pierce point is from the bore centreline? Just looking and visually the valves are way low, maybe 1/4" inch? How far did the valves have to be moved to centre them on some of the Mopar race heads?

Intake = 1.15" from bore centerline
Exhaust = .93" from bore centerline
Horizontal centerline for both valves = .3146"toward the exhaust side from bore centerline

This I believe is backwards. On the valve pierce points but perfect on the offset from wristpin axis.

[Walter R. Malik]

Doing some research on big block Mopar heads for a project I am working on. Does anyone have a head blueprint they are willing to share? And/or know the distance the valve pierce point is from the bore centreline? Just looking and visually the valves are way low, maybe 1/4" inch? How far did the valves have to be moved to centre them on some of the Mopar race heads?

Intake = 1.15" from bore centerline
Exhaust = .93" from bore centerline
Horizontal centerline for both valves = .3146"toward the exhaust side from bore centerline

This I believe is backwards. On the valve pierce points but perfect on the offset from wristpin axis.

The print I took it from must be labeled wrong.
But, yes, the intake centerline should be closer to the bore centerline.

[Erland Cox]

I once made a shrouding calculator in Excel:

http://www.topplocksverkstan.se/ventils ... spalt.html


Erland