on normal, you would have to do pure research for over a decade to ever max out. O.o
do the calculations if you dont believe me. :)
If you started at a research level of 25 (which I think is when it gets to like 750 turns per level), then to get to lvl 100 (which I think is when it turns to 2500 a level), it would be 56250 turns. from 101 to 255, it would take 387500 turns. So the combined total would be 443750 turns.
at 15 minutes a turn (normal), it would be 6656250 minutes of pure research, which translates to about 4623 day rounding up, which is about 12.67 years (12 years, 8 months aprox)
on fast at 5 minutes a turn, that would end up being 1541 days, which is about 4 years, 3 months. At 2 minutes a turn, that would be 617 days.
On RT server, it would take 987 hours, which, if you spent 3 hours a day of pure research, you would be done in about a year. :P
A bit of boring math for u GC freaks. =)
Naturally, this doesnt include tech research or the first 25 levels of research. =)