When you say it takes around 1 min to do one request - what is that request doing? Sounds like a PHP script is messing up / taking a long time to process.

I doubt very much its a hardware or location based issue, but to rule it out you can do some simple steps:

1. Ping your server (should give you a transit time)
2. Try requesting a basic HTML page eg. a "Hello World" page and see how long that takes

I guess you need to get a good cache plugin. Every request on your server is processed as new req. Cache plugins can drastically up your server progress. Even I'm using cache on my site to speed up the loading time.