I am using Tor with Google Chrome to bypass government censorship. Does polipo increase my surfing speed or chrome do the caching itself?
Does Polipo increase my surfing speed or chrome do the caching itself?
Unless you disabled your Chrome-caching they are both caching.
Do I actually need Polipo with Tor?
Polipo is useful for content filtering. It won't help unless you set it up to do some filtering. You might also find Privoxy useful for similar content filtering (but non-caching proxy).
Is there a reason you would rather use Chrome than Tor Browser?