Unexpected http.request behavior.

client.js

var http = require('http');

var headers = {
    'x-apikey': 'blah'
    //'connection': 'keep-alive'
};

var options = {
    host: 'localhost',
    port: 1337,
    headers: headers,
    method: 'POST',
    path: '/'
};

var req = http.request(options, function(res) {
    res.on('data', function (chunk) {
        console.log(chunk + '');
    });
});

req.on('error', function(error) {
    console.log(error);
});

req.on('socket', function(socket) {
    var interval;
    socket.on('connect', function() {
        var i = 0;
        //Uncommeting setInterval block makes it work as expected.
        //interval = setInterval(function() {
            i++;
            req.write(i + ' - yo client!\n');
        //}, 0);
    });

    socket.on('close', function() {
        clearInterval(interval);
        console.log('socket closed');
    });
});

req.write('\n');

server.js

var http = require('http');

http.createServer(function (req, res) {
    res.writeHead(200, {'Content-Type': 'text/plain'});

    var interval = setInterval(function() {
        console.log('sending data...');
        res.write('Hello World\n');
    }, 1000);

    req.on('close', function() {
        console.log('client request closed');
        clearInterval(interval);
    });

    req.on('data', function(chunk) {
        console.log(chunk + '');
    });
}).listen(1337, "127.0.0.1");
console.log('Server running at http://127.0.0.1:1337/');