node.js vs IIS 7.5 performance

The setup:

2 machines on EC2 of type m3.xlarge.

First one with ubuntu server.

Second one win2008r2.

node.js on ubuntu using the basic example to return a string response to any request.

asp.net httphandler to return the same response.

using https://github.com/newsapps/beeswithmachineguns I used 10 machines to execute 200000 with concurrency of 2000 (200 per machine) I ran the benchmark and got:

NodeJS:

 Complete requests:         200000

 Requests per second:       5605.170000 [#/sec] (mean)

 Time per request:          358.071900 [ms] (mean)

 50% response time:         31.000000 [ms] (mean)

 90% response time:         239.300000 [ms] (mean)

IIS:

 Complete requests:         200000

 Requests per second:       9263.810000 [#/sec] (mean)

 Time per request:          215.992900 [ms] (mean)

 50% response time:         214.000000 [ms] (mean)

 90% response time:         244.000000 [ms] (mean)

The nodeJS code is:

http.createServer(function (request, response) {
  response.writeHead(200, {'Content-Type': 'text/plain'});
  response.end('Some response\n');
}).listen(80);

The httphandler code is:

context.Response.Write("Some response\n" + Guid.NewGuid().ToString("N"));

I thought node js will be much faster, did I do something wrong?

EDIT:

after using the cluster module I got 16685 request per second from the node js I"m going to bring up the strongest EC2 instances and check on them