Ran into the same problem with 30,000 records.
Sugar's import is a real memory hog and it needs time to process. You need to bump up your max_execution_time, max_input_time, and memory_limit settings *significantly*...
So, in your php.ini try this:
max_execution_time = 3000 ; Maximum execution time of each script, in seconds
max_input_time = 6000 ; Maximum amount of time each script may spend parsing request data
memory_limit = 386M
Even with *these* settings - I still had to break up my import into 5,000 record chunks...
Memory is a major player in this. In other words, once I put my execution_time and input_time to these levels, any further increase didn't help. However, memory *did*. So, if you can allocate a gig of ram, I'll be you'll be able to import your 8,000 records in one shot.
-John
www.progresspays.com