Okay, I am new to AdvanceMame (see the main forum for some timings I did on various speed computers).
I found a web site (I'll post it later once I find the URL again)
It suggested not using EMM386 and instead something like UMBPCI.SYS .
On a cruddy old P166/16 meg system it took almost 3 minutes to load AdvanceMame 83 and BTIME.ZIP to get to the OK screen.
When I added EMM386.exe (or replaced UMB.sys) the load time went to about 9 minutes, using the settings listed above.
I'll have to try some other stuff too. I know there isn't much hope with such a new .83 version and a P166/16 meg but I am just using it as a baseline for what the worst system is and what it takes to speed it up as much as possible, and then apply the same info to faster systems.