Hi,
Unfortunately it is not possible with current Virtumeart,
Because Virtuemart doesn't have any "custom" field for product details page,it has "product description" and "short description" only, and that's it. We just brought thing little further and pre-created the "specifications" TAB which include the "non-cart variant" custom fields. But that's all, if you want to add more, such as; "shipping info" or anything like that, you would need lots of coding changes and MySQL modifications; which will be the HACK of virtuemart and wouldn't be recommended.
Cheers.
Support Desk.