Adding a 100amp subpanel, total run is about 70 ft - and 1 1/4 Sch40 PVC is already in the ground. There are a fair amount of turns, it looks like:
Main Panel -> out rear hole through wall -> Pull box -> 90 -> 90 -> Pull box -> 45 -> 45 -> 45 -> 90 -> Sub Panel.
Trying to decide what cable to run for feeders. Initially was thinking 3 @ #3 Copper THHN and #6 Bare Ground as it would be thinner and easier to pull - especially due to the (45,45,45,90) run under concrete.
Then I read that XHHW is more flexible despite being slightly thicker (can't tell if this is true or good marketing) and of course #2 AWG Aluminum is an option - which I dismissed as being too hard to pull in 1 1/4" conduit with those bends.
Any practical advise for how hard it would be to get #2 Aluminum through those bends and/or if I should consider XHHW?
("Pull box" is a LB Conduit Body)
[Edited] Edited original post - I meant to say #3 Cu vs #4. My calc for #3 was assuming a QO 125Amp Sub panel (75C rating) and then I adjusted for ambient (Using 310.15(B)(2)(a)) by 1.11 (all underground and our average air is 58F) and ended up with 111 amp at 75C.