rebuilt 360 oil loss HELP!

I'm new to the forum and in need of help. I have a rebuilt 71 360: new ring,pistons,cam,values,v.seals. I have put about 1500 miles on it. It is lossing oil and its not leaking on the floor or anywhere else. I notice white smoke on crank up (not alot) and when speeding up 55+. Seems like it is only coming out of the right exhaust.I have gone though about 6 quarts since the rebuild. There is no peformance loss.Can any one point me in the right direction?

Thanks
Aaron