There are plans circulating around for several different sized frames. This can be confusing.
"Book" frame refers to the frame in Ron Champion's book. That frame is 42" wide, 13" tall and 116" long. It can be considered the locost "standard" if there is one.
http://mcsorley.net/locost/drawings/bookChassis.pdf (Download plans here)
Then you have the McSorley frames.
+4 is a "book" frame with 4" added right down the middle. Same height and length as a "book" frame only wider.
http://www.mcsorley.net/locost/drawings/McSorley7+4.pdf (Download plans here)
+442 is another modified "book" frame. Mcsorley added 4" of width from the front bulkhead back, 4" of length, and two inches of height from the cockpit forward.
http://mcsorley.net/locost/drawings/McSorley7+442.pdf (Download plans Here)
The Collins frame is a +241.
http://www.locostusa.com/files/Collins.pdf (Download plans here)
The Gibbs/Haynes Roadster frame is a reletively new design based around the UK Sierra and US XR4TI IRS. There is a entire set of
forums dedicated to this chassis and Chris Gibb's
book about it. The Gibbs / Haynes Roadster frame is right about +221.
There's another version of the +442 frame which is the +442E.
The +442E is 4" wider throughout the entire length, which seems to be suitable for larger motors / drivetrains. +442E example -
http://www.locostusa.com/forums/viewtopic.php?t=1586
Relevant discussions:
http://www.locostusa.com/forums/viewtopic.php?t=803
http://www.locostusa.com/forums/viewtopic.php?t=1590