Trading Dow Futures.. Is my system +EV?

[wickedgoodtrader]

Ive been trading dow futures for about 6 months now. I started off with a system I bought over the net and was doing really well then the dow got real volatile and I kept gettin stopped out and lost most my profits back. So I quit the system.

I'm now working on my own system. It's very simple. I have read 1 beginners day trading book and it said how half hour before the close the market tends to pick a direction and go with it. Of late... this has been very true. I decided to closely watch the candlestick chart on DIA around 3:30 to see which direction it looks to be heading. I then go long or short and close the position seconds before the bell.

I made 4 trades in the last week all winners and profiting $15,000 on 10 contracts of the $5 mini-dow. I know they all can't be winners but I'm really trying to figure out if this is +EV. Like if there's a way to backtest it or something. Any ideas/comments from anyone with more experience on wether they think this strategy can be profitable?