also, Youngengines has done a ton of R&D and on his dyno and he has threads floating around with great info... i had a thread on a basic/stock bore and stroke, but expensive hemi build, but it seems to be gone since the new site.. some people get away with using more stock parts... and i have built a ton of these basic motors in the past... for my self, kids, friends, etc... I had no issues with the parts as far as "bolt on"/safety, but they were never "fast" enough for me, so i tend to get into much more expensive builds now...
much bigger displacement projects including the vtwin... long as you set your goal and stick to it, then you will have fun cruising around on the basic motor... if you think you want to race etc... then you may need a "little more"...