SPDY module is designed to only work with secure connections (SSL-enabled websites).
I want to know there is any fork of that project (specifically MOD_SPDY for apache) which bypasses SSL and works over non-secure HTTP (and not HTTPS) connections?
If no, is it possible to modify and rebuild the source (easily!) for that purpose?
It's unlikely, since the protocol specifies transport security, even if you could gut
mod_spdy
to not need it, no client is going to make a connection without TLS anyway.