Simply notify ATC on the AWC freq that you cant meet the
min alts on the XXX SID. Theyll ether issue a new SID or say
to expect radar vectors after TO. Or just tell them the SID
that meets with your performance.
This differs from the Engine-Out proc which doesnt necesarily
follow a SID. Mainley used when published SID min alts or
obst clearance alts cant be met.
For light ac refer to the perf graphs/charts in the AFM.