Valve Train Deflection

Which valve train component deflects the most in an American OHV V8 ?


  • Total voters
    4

Indycars

Administrator
Staff member
Found an article on the subject and it gives deflection numbers by component.

Vote on the component that you think deflects the most and later I will post the article with all the info and numbers.
 
in many cases Id go with a combo of both pushrod and rocker stud deflection

media.nl
 
Last edited:
The answer to my question above is the Rocker Arm. You can read the full article by using the link below.

https://blog.trendperform.com/spintron-secrets-valve-float-bounce-and-loft-explained

Quote From Article:
“You can get a lot of deflection on the opening side of the valve motion curve,” Brown explains. “All the parts
have some deflection and in an overhead rocker system, the rocker can be up to 40 percent of the total
deflection due to it being the only component that’s in bending where all other components like the pushrod
are in compression.

ValveTrainDeflectionComponents.jpg
.
 
Id bet that charts referring to the OEM, stamped sheet metal rockers,
I just don,t think the better aftermarket roller rockers would be that flexible
notice the chart indicates about .004 thousandths in rocker arm deflection


longslot.jpg



rockert2.jpg

rockert33.jpg

rockert44.jpg

Rockerarmextreme.jpg
 
Id bet that charts referring to the OEM, stamped sheet metal rockers,
Probably right Grumpy, the article really didn't go into any details. But it did make me think about
the valve train and I thought it was interesting that the rocker is the only component subjected to
bending stresses. Everything else is in compression according to the article.

What about the camshaft, I guess it is subjected to shear forces or is that not also bending ???
 
What about the camshaft, I guess it is subjected to shear forces or is that not also bending ???

I thought that the cam would have a small amount of flex to it also. I would not have thought that the rockers would flex, with the way they are shaped. My second guess would have been the pushrod... I learned something today.. Thanks Rick
 
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