I will read up on P0 behavior, also i have a 8052 with internal ram. Will this help any like you suggested?

I hope you mean flash/eprom

If you use such a uC P0 will ONLY be a data port for the A/D data = no timing issues. Remove the prom and the ALE latch (you can leave the latch, but the prom must go.

Decide if you want to fight the P0 timing issues. Also since the pin that enables A/D output will be true during (at least) a few code fetches - one of the following will happen
a) a blown A/d
b) a blown code memory
c) malfunctioning code
d) no problem

I do not know, a wild guess would be c)

If you want to keep using external memory, you need to make the A/D memory mapped I/O.

Erik