Big Block Mopar valve offset
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Big Block Mopar valve offset
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?
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Re: Big Block Mopar valve offset
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
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
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Re: Big Block Mopar valve offset
Intake = 1.15" from bore centerlineKen_Parkman wrote: ↑Tue Dec 06, 2022 7:36 pm 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?
Exhaust = .93" from bore centerline
Horizontal centerline for both valves = .3146"toward the exhaust side from bore centerline
http://www.rmcompetition.com
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Specialty engine building at its finest.
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Re: Big Block Mopar valve offset
This I believe is backwards. On the valve pierce points but perfect on the offset from wristpin axis.Walter R. Malik wrote: ↑Tue Dec 06, 2022 8:18 pmIntake = 1.15" from bore centerlineKen_Parkman wrote: ↑Tue Dec 06, 2022 7:36 pm 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?
Exhaust = .93" from bore centerline
Horizontal centerline for both valves = .3146"toward the exhaust side from bore centerline
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Re: Big Block Mopar valve offset
The print I took it from must be labeled wrong.DCal wrote: ↑Wed Dec 07, 2022 12:07 amThis I believe is backwards. On the valve pierce points but perfect on the offset from wristpin axis.Walter R. Malik wrote: ↑Tue Dec 06, 2022 8:18 pmIntake = 1.15" from bore centerlineKen_Parkman wrote: ↑Tue Dec 06, 2022 7:36 pm 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?
Exhaust = .93" from bore centerline
Horizontal centerline for both valves = .3146"toward the exhaust side from bore centerline
But, yes, the intake centerline should be closer to the bore centerline.
http://www.rmcompetition.com
Specialty engine building at its finest.
Specialty engine building at its finest.
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Re: Big Block Mopar valve offset
I once made a shrouding calculator in Excel:
http://www.topplocksverkstan.se/ventils ... spalt.html
Erland
http://www.topplocksverkstan.se/ventils ... spalt.html
Erland