It is ideal to choose a non-magnetic element (Y227) in R2Ir2O7 series to investigate Ir. We have found the low-lying spin fluctuations in Nd2Ir2O7 from LF-muSR reflecting the 4f-5d exchange interaction between Nd and Ir. We got the four-days beam time to carry out ZF-muSR on (Y0.95-xCu0.05Cax)2Ir2O7 to determine the magnetic phase diagram but this is not good enough to investigate detail changes in the spin dynamics by changing samples, temperatures, and magnetic fields. We would like to propose additional beam times on 4 key samples with x=0, 0.10 (insulating with some doping), 0.15 (~QCP) and 0.20 (metallic). We expect to observe low-lying spin fluctuations even within 4kG range at low temperatures following our result on Nd2Ir2O7 to study mainly the spin-dynamics related to Ph.D. thesis of one of our members and we are planning to publish the data together with transportation results