big wait time server response

For months I'm having a big problema with my website. That's why I was trying to change my server. I'm using the gavick sporter template and mod_news module.

I don't know why but my website is too late to load. Independent of the server, the site is too slow to load. I've already activated css/s compression, cache, thumbs genaration, cleaned up html code, but the performance still poor.

I'm thinking that is something related to the template. I have 3 identical sites in three differente servers:

http://www.portaldorugby.com.br (server 1 in Brazil)
http://54.243.216.226/ (server 2 in USA - amazon Ec2)
http://54.232.123.233/ (server 3 in Brazil - Amazon EC2)


Independent of the link, any page of the site is slow to load 100%.

Can you help me?

tks

I forgot to say, but when I'm accessing the backend, the wait time reduces a lot.