I made various speed tests to my website via webpagetest.org and I used a mobile network in California (which I believe is the closest one to google) to measure the speed of my site. It reports the time to first byte as an average between 100 and 150ms. My server is in East Canada.
I then proceeded to use Search console (google webmaster tools) to test the same page in the same state (uncached) and the download time is about 75ms.
I want to be able to use a client on webpagetest.org that best represents googlebot when it comes to testing page speed so I know where I stand in google's index because speed is a factor for ranking high.
So which server, browser, and connection type (and other details) do I use on webpagetest.org to mimic googlebot in terms of speed testing?