You cetainly can put the Z limbs and cams on an Onza. Almost all the parts are interchangeable. You don't need to get fancy on strings and cables either. Use standard lengths for the Onza with Nitro cams. Nitro and Hybrix are identical. The only difference you might see is that with the shorter bow the draw weight range is going to be higher. 5# or maybe even 10#, not sure on how much. Call Joel and he'll be able to tell ya.
Do you have a typo concerning the limb deflection? You're saying you have 5X. Are you sure they don't say 5MP or 5HP or something like that? Last year I ordered a set of 50# limbs for my Nemisis, virtually the same as the Onza, and they sent me 3MP limbs. Just using this as a guideline I'd think that #5 limbs would be for 60#. Hope it works that way. I'd hate for them to be 70# and you end up with an 80# Onza.
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