I'm not sure about a website where you plug in your stats and it gives you results (never heard of it personally).
The best I can do is a review of the 760 ACX http://www.techpowerup.com/reviews/EVGA/GTX_760_SC_ACX_Cooler/1.html
It has 17 games tested and the setup for the charts is 8 gigs of DDR3 1600 with an i7 4770K at 4.2ghz which isn't a ton faster than what you have now in terms of CPU (you should get within 5-10% of the results on the benchmark on most games).
that is slightly disconcerting, i would rather like better performance from metro last light, i swear everytime i settle on a GPU i end up upping the budget again
You can't get upset over the developers mistake (that's a bad habit that can lead to upgrading/buying parts you don't need).
Metro Last Light is a low budget game that's poorly optimized. Even with the poor optimization, the GTX 760 is able to get 45-48FPS average on very high settings with tessellation (along with most of the other advanced options) turned on
Your getting about 90% of the graphics potential on a poorly optimized game while still getting good frames