UPD: Not close question because I think my way is not so clear as should be
Is it possible to get current request + response + download time for saving
You could write a Downloader Middleware which would time each request. It would add a start time to the request before it's made and then a finish time when it's finished. Typically, arbitrary data such as this is stored in the Request.meta attribute. This timing information could later be read by your spider and added to your item.
This downloader middleware sounds like it could be useful on many projects.