pls find the attachment of my query, and provide your suggestions ASAP
the issue here is your desire to understand the EIGRP metric.
Here are some notes about EIGRP way to calculate metrics
256 * (sum of delays in 10s of microseconds)
256 * (500 +2000+2000) = 1152000
256 * (4500)= 1152000
bw component is the inverse of the smallest BW in the path in kbps
256 * 10^7 / 1544 = 1658031
total = 2810031
not so different from 2809856 that appears in your routers.
Again FD is the best metric from the point of view of the local node (R4)
EIGRP metric is cumulative in delay but inverse proportional to the lowest BW in path so the fact that R1's loop0 has BW 8000000..... kbps has no effect in EIGRP metric calculation.
other point is that you need to divide by 10 the value you read of delay in the various sh interface because EIGRP uses tens of microseconds
Hope to help