Nodejs async versus sync method load test

I have been trying to create a view module for an MVC framework.

I have 2 versions of code. One that does Sync and one Async.
I know that i should be using the Async version. However whenever I do a loadtest via AB I'm getting better results from the Sync version.

Am I doing something wrong? This is a sample of the code I'm testing

Sync Version:

var fs = require('fs'),
    path = require('path'),
    dot = require('dot');
    Step = require('../libraries/step.js');

var view = function(){};

view.prototype = {

    renderView : function(source, data, layout, callback)
    {
        var self = this;

        if (typeof callback !== 'function') throw ViewCallbackException;

        layout = layout ? layout : 'default';

        (function(sources, datas, layouts, callbacks)
        {
            content = fs.readFileSync('./views/layouts/' + layouts + '/index.html', 'utf-8');
            callbacks(null, content);
        })(source, data, layout, callback);
    }
}

Async Version:

var fs = require('fs'),
    path = require('path'),
    dot = require('dot');
    Step = require('../libraries/step.js');

var view = function(){};

view.prototype = {

    renderView : function(source, data, layout, callback)
    {
        var self = this;

        if (typeof callback !== 'function') throw ViewCallbackException;

        layout = layout ? layout : 'default';

        (function(sources, datas, layouts, callbacks)
        {
            Step(
                function()
                {
                    fs.readFile('./views/layouts/' + layouts + '/index.html', 'utf-8', this);
                },
                callbacks
            );
        })(source, data, layout, callback);
    }
}