The benchmark[1] includes scimark, which measures FLOPS. I get 0.62 MFLOPS. In scimark running in the JVM[2], I get 353.4 MFLOPS (units explained here[3]). So in conclusion, the Oracle JVM on x86-32 is 570 x faster than lua.vm.js on V8 on same platform.
[1]: http://kripken.github.io/lua.vm.js/lua.vm.js.html
[2]: http://math.nist.gov/scimark2/run.html
[3]: http://math.nist.gov/scimark2/faq.html