40 deg total adv ???? Hmmm

I am running a mopar 528 mech purple stick---Car is running good-no knock but I checkrd my timing and total is 40 deg all in at 2500rpm ???? Should be 36 deg right???
Is 40 to much total my initial is 16
440
forged pistons
all the goodies
auto 3000 stall
Mech dist
Your at its max limit, go no more. have fun.
small bocks no more than 50, total.