disassembling I noticed that the balance wheel 2 different symbols 8 has a triangle down and 8 a triangle up

to see you it seems that the profile changes but I have not found anything on their psition

I believe that is just a manufacturer's mark. There is no difference between the intake and exhaust rockers, unless someone has changed the ratio....

Joel Adams  
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

if the ratio has been modified do I have to replace the wrong ones?

If you are not sure of the ratio of the rocker arms you have, I would suggest replacing them all if possible. If all of the ones you have measure exactly the same from pushrod pocket to valve stem end, and you don't have any damaged valve springs, then run them as they are.

Joel Adams  
My Link

    
(click for Texas-sized view!)             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"