Senior friend was asking for a stronger core in 13# equipment. There seems to be quite a dropoff in diff iin 14 down to 13. Do any ball companies offer a true asymetrical core in 13# equpment. Seems like companies that offer 13# use a generic core when under 14# balls. Thanks for advance for your input.

Thirtyclean

Brunswick has one of the stronger asym cores in their lighter weight equipment.  For example, the DV8 Intimidator has a .016 asy diff in the 14#, and .014 in the 13#.

The Hammer Redemption line (made by Brunswick) has a .015 in the 14# and a .014 in the 13#. 

Older, pre-Brunswick EBI made balls are NOT very good on the asym side.  They would literally not make the 12# and 13# versions of asym balls asymmetrical at all.  They would be symmetrical and not even have the MB indicator on the ball.  Once Brunswick took over, the dynamics of the lighter weight balls has started improving dramatically.

Brunswick is one of the best manufacturers for maintaining dynamic integrity in the lighter weight balls.  While the core shapes are not the same, the dynamic specs are close enough that the effect on ball reaction is minimal.

As someone who throws 13 lbs, I am always looking at this. Storm also shows cores used at each weight on their website

Motiv says they use same shape core at all weights but their stronger balls do not come lighter than 14. That said, numbers on Trident Nemesis are

2.56/.051/.015

Those are strongest numbers I think I have ever seen on a 13 lb ball

Numbers aren't as good on those rotos but that's the theory core

Friend of mine got the rubicon in 13#, and it had that same core in it. He drilled it strong, and was amazed at the amount of flare he got.