I have a bunch of walnut layin around iv decided to use it for my recurves.  I am thinking of trying a new core in my lams.  Would a parallel and tapered bamboo between veneers and glass produce a powerful limb or would one maple parallel and one tapered boo (or vise versa) produce better results?  

You probably could not tell the difference.  Kennym did a performance test by building several different bows with the lams being the only difference.  It's probably on the first page.

Thank you.