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> Double spring/.460 + lift cam, Hard to turn over engine?
rfinegan
post Jun 29 2021, 06:28 AM
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I am working on my 2056 build and have been setting my valve and pushrod geometry with light weight springs and turning the engine over by the flywheel with the plugs out with out issue. This is one cylinder / valve at a time.

I now have the double springs installed and started to install the pushrods and rockers. I am finding the valve springs on the cam lobes will roll the engine backwards when releasing the fly wheel. Multiple valves lashed I need 2 hands( slightly exaggerated ) to turn the engine over. Still no plugs. Flywheel holder /turner is better but....

Just checking is if this is still "NORMAL" as I button up the valve covers shortly

-Best Regards

-Robert
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Mark Henry
post Jun 29 2021, 10:54 AM
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QUOTE(rfinegan @ Jun 29 2021, 08:28 AM) *

I am working on my 2056 build and have been setting my valve and pushrod geometry with light weight springs and turning the engine over by the flywheel with the plugs out with out issue. This is one cylinder / valve at a time.

I now have the double springs installed and started to install the pushrods and rockers. I am finding the valve springs on the cam lobes will roll the engine backwards when releasing the fly wheel. Multiple valves lashed I need 2 hands( slightly exaggerated ) to turn the engine over. Still no plugs. Flywheel holder /turner is better but....

Just checking is if this is still "NORMAL" as I button up the valve covers shortly

-Best Regards

-Robert


Install all the springs and it should't roll back. Yes it will take some effort, but there should be no binding rolling it over 720 degrees.
Did you check clearance between the guide and retainer? What height and pounds did you set the springs for?
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rfinegan
post Jun 29 2021, 04:11 PM
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QUOTE(Mark Henry @ Jun 29 2021, 08:54 AM) *

Guide to retainer should not be a problem as I rolled the engine over several times in the running direction with the light springs.
I also tested the Piston to Valve clearances (as I can press the valve) at multiple locations on the cam lobe. NO issues and lots of travel even at full lift

Will follow up on the Installed Height and spring stack and spring weight

As always...Thank you Mark

I think it will be balanced forces once all the pushrods are installed and lashed


QUOTE(rfinegan @ Jun 29 2021, 08:28 AM) *

I am working on my 2056 build and have been setting my valve and pushrod geometry with light weight springs and turning the engine over by the flywheel with the plugs out with out issue. This is one cylinder / valve at a time.

I now have the double springs installed and started to install the pushrods and rockers. I am finding the valve springs on the cam lobes will roll the engine backwards when releasing the fly wheel. Multiple valves lashed I need 2 hands( slightly exaggerated ) to turn the engine over. Still no plugs. Flywheel holder /turner is better but....

Just checking is if this is still "NORMAL" as I button up the valve covers shortly

-Best Regards

-Robert


Install all the springs and it should't roll back. Yes it will take some effort, but there should be no binding rolling it over 720 degrees.
Did you check clearance between the guide and retainer? What height and pounds did you set the springs for?

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rfinegan
post Jul 12 2021, 04:39 AM
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UPDATE:

I installed the last of my push rod tubes and push rods, rockers, etc. Set my valve lash to about 001-002 for just a little audible click and feel of movement. I will ZERO lash after break in. The engine rolls over fine. It's smooth and consistent with out the roll back observed with only one cylinder with push rods and springs.

NOTE to new users: Double springs have a LOT of pressure on valve train. That is why they are used with High lift cams and large valves to keep those components in control at higher speed!

Turning my 2056 with no plugs is EZ with a fly wheel tuner/holder. Not so EZ by hand at the flywheel (it was very EZ with just the rotating assembly less heads)

I Feel Im normal Again (for this 2056)
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